Karl Herzfeld
Encyclopedia
Karl Ferdinand Herzfeld was an Austria
n-American
physicist.
. His mother, Camilla née Herzog, was the daughter of a newspaper publisher and sister of the organic chemist R. O. Herzog.
In 1902, when Herzfeld was 10 years old, he was enrolled in the private Gymnasium
Schottengymnasium, which was run by the Benedictine Order of the Roman Catholic Church
and had its name derived from the fact that the founders came from Scotland
. He attended this school until 1910, when he began attending the University of Vienna
to study physics
and chemistry
. In 1912, he took courses at the University of Zurich
and the Eidgenössische Technische Hochschule Zürich (ETH). It was in Zurich he met Otto Stern
, who was at the ETH; Herzfeld later credited conversations with Stern for his deeper understanding of thermodynamics. In 1913, he went to study at the University of Göttingen, after which Herzfeld returned to Vienna, and was granted his doctorate in 1914, under Friedrich Hasenöhrl
, who had become Director of the Institute for Theoretical Physics, upon the suicide of Ludwig Boltzmann
in 1906.
Herzfeld’s doctoral thesis applied statistical mechanics to a gas of free electrons as a model for a theory of metals. By the time he received his doctorate, he already had published six scientific papers. In one of them, he attempted to derive a model of the hydrogen atom. This paper was published in 1912, shortly before Niels Bohr
submitted his first paper on the Bohr model
of the hydrogen atom.
Upon receipt of his doctorate, Herzfeld volunteered for service in the Austro-Hungarian Army. World War I
broke out shortly thereafter and he served until 1918, rising to the rank of first lieutenant. Herzfeld’s thesis advisor Hasenöhrl was called to serve during World War I and was killed at the front. During his tenure in the military, Herzfeld published six papers on statistical mechanics
applied to problems in physics and chemistry, especially to the structure of matter – gases, liquids, and solids.
After the War, Herzfeld returned to the University of Vienna, however, the University was in such dire financial straits that he moved to Munich in 1919, with the intent of studying analytical chemistry and getting a job in the German chemical industry, which had a highly respected reputation. First, he was an assistant at the physico-chemical laboratory of Kasimir Fajans at Ludwig Maximilians University of Munich
(LMU). However, once there, he found the challenge of theoretical physics more to his liking. He became Privatdozent
for theoretical physics and physical chemistry at LMU, and therefore was much more associated with Arnold Sommerfeld
, who was ordinarius professor for theoretical physics and Director of the Institute for Theoretical Physics – a prominent organization for the study of atomic and molecular structure. From 1925, until he left LMU in 1926, he was extraordinarius professor of theoretical physics. During this time, Linus Pauling
did postdoctoral studies with him, and he was the thesis advisor for Walter Heitler
, who got his doctorate in 1926. In 1925, Herzfeld published his book on kinetic theory and statistical mechanics, which became a graduate-level textbook in German-speaking universities.
in Baltimore
, Maryland
, which developed into a regular faculty position. During 1930 and 1932, he was a lecturer at Cooper Union
and Fordham University
in New York City
.
While at Johns Hopkins, Herzfeld did considerable research with the chemist Francis O. Rice, who joined the University as an associate professor the same year Herzfeld arrived. Their 1928 paper considered the role of molecular vibrations in the transfer of energy between ultrasonic waves and gas molecules. At Johns Hopkins, Herzfeld worked with other European colleagues on the University’s physics faculty, namely James Franck
and Maria Goeppert-Mayer, who were awarded Nobel Prizes in Physics
in 1925 and 1963, respectively. Franck came to Johns Hopkins after he left Germany in 1933, where he had been ordinarius professor of experimental physics and Director of the Second Institute for Experimental Physics at the University of Göttingen and a close colleague of Max Born
, who was Director of the Institute of Theoretical Physics at Göttingen. Goeppert-Mayer was a student of Born, and she joined the Johns Hopkins faculty in 1931. Goeppert-Mayer and Herzfeld published articles on states of aggregation and nuclear fusion reactions. Herzfeld coauthored articles with Franck on photosynthesis, one being after they had both left Johns Hopkins. John Archibald Wheeler
, who became a prominent physicist, took his PhD under Herzfeld in 1933.
In 1936, Herzfeld moved to The Catholic University of America
in Washington, DC, where he remained until his death in 1978. He received emeritus
status in 1969 and stayed active for the rest of his life.
Reasons for Herzfeld leaving Johns Hopkins were described in a letter to Arnold Sommerfeld. A main reason was the dire financial situation at Johns Hopkins. However, there were other reasons as well. One being his relationship with R. W. Wood, a professor of experimental physics and chairman of the physics department, had deteriorated. Also, J. A. Bearden, another experimentalist, thought there was too much emphasis on theoretical physics and the number of German physicists in the small department was out of balance. Bearden also suspected that Herzfeld had brought Franck to Johns Hopkins to further Herzfeld’s ambitions to be department chairman. Finally too, Bearden thought Herzfeld had caused dissension in the department over his strong support to promote Göppert-Mayer from research associate in physics to a regular faculty appointment. While Herzfeld did receive offers from both Fordham University and Catholic University, neither was appealing as they did not have strong research departments. While talking the situation over with Isaiah Bowman
, president of Johns Hopkins, it became clear that the financial difficulties at Johns Hopkins might require downsizing the physics faculty. With this in mind, Herzfeld accepted the offer from Catholic University. Herzfeld’s teaching responsibilities and salary at Catholic University were about the same as that at Johns Hopkins, but there were additional administrative duties, as he was also chairman of the physics department.
In 1938, Herzfeld married Regina Flannery, who was an instructor at Catholic University; by the time she retired in 1970, she had risen to professor and head of that department.
In the late 1940s, Herzfeld increased the attention at Catholic University to quantum-mechanical calculations on the electronic structure of polyatomic molecules, thus establishing a respected position for the University in this field.
In 1959, Herzfeld and Theodore A. Litovitz collaborated on a book, in part, summarizing Herzfeld’s thinking on ultrasonics over the 30 plus years since his article with F. O. Rice. In 1966, Herzfeld published a review article summarizing 50 years of developments in physical ultrasonics.
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
n-American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
physicist.
Education
Herzfeld was born in Vienna during the reign of the Habsburgs over the Austro-Hungarian Empire. His father was a physician and ordinarius professor of obstetrics and gynecology at the University of ViennaUniversity of Vienna
The University of Vienna is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world...
. His mother, Camilla née Herzog, was the daughter of a newspaper publisher and sister of the organic chemist R. O. Herzog.
In 1902, when Herzfeld was 10 years old, he was enrolled in the private Gymnasium
Gymnasium (school)
A gymnasium is a type of school providing secondary education in some parts of Europe, comparable to English grammar schools or sixth form colleges and U.S. college preparatory high schools. The word γυμνάσιον was used in Ancient Greece, meaning a locality for both physical and intellectual...
Schottengymnasium, which was run by the Benedictine Order of the Roman Catholic Church
Roman Catholic Church
The Catholic Church, also known as the Roman Catholic Church, is the world's largest Christian church, with over a billion members. Led by the Pope, it defines its mission as spreading the gospel of Jesus Christ, administering the sacraments and exercising charity...
and had its name derived from the fact that the founders came from Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
. He attended this school until 1910, when he began attending the University of Vienna
University of Vienna
The University of Vienna is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is the oldest university in the German-speaking world...
to study physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
and chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
. In 1912, he took courses at the University of Zurich
University of Zurich
The University of Zurich , located in the city of Zurich, is the largest university in Switzerland, with over 25,000 students. It was founded in 1833 from the existing colleges of theology, law, medicine and a new faculty of philosophy....
and the Eidgenössische Technische Hochschule Zürich (ETH). It was in Zurich he met Otto Stern
Otto Stern
Otto Stern was a German physicist and Nobel laureate in physics.-Biography:Stern was born in Sohrau, now Żory in the German Empire's Kingdom of Prussia and studied at Breslau, now Wrocław in Lower Silesia....
, who was at the ETH; Herzfeld later credited conversations with Stern for his deeper understanding of thermodynamics. In 1913, he went to study at the University of Göttingen, after which Herzfeld returned to Vienna, and was granted his doctorate in 1914, under Friedrich Hasenöhrl
Friedrich Hasenöhrl
Friedrich Hasenöhrl , was an Austro-Hungarian physicist.-Life:Friedrich Hasenöhrl was born in Vienna, Austria in 1874. His father was a lawyer and his mother belonged to a prominent aristocratic family...
, who had become Director of the Institute for Theoretical Physics, upon the suicide of Ludwig Boltzmann
Ludwig Boltzmann
Ludwig Eduard Boltzmann was an Austrian physicist famous for his founding contributions in the fields of statistical mechanics and statistical thermodynamics...
in 1906.
Herzfeld’s doctoral thesis applied statistical mechanics to a gas of free electrons as a model for a theory of metals. By the time he received his doctorate, he already had published six scientific papers. In one of them, he attempted to derive a model of the hydrogen atom. This paper was published in 1912, shortly before Niels Bohr
Niels Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in...
submitted his first paper on the Bohr model
Bohr model
In atomic physics, the Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with electrostatic forces providing attraction,...
of the hydrogen atom.
Upon receipt of his doctorate, Herzfeld volunteered for service in the Austro-Hungarian Army. World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
broke out shortly thereafter and he served until 1918, rising to the rank of first lieutenant. Herzfeld’s thesis advisor Hasenöhrl was called to serve during World War I and was killed at the front. During his tenure in the military, Herzfeld published six papers on statistical mechanics
Statistical mechanics
Statistical mechanics or statistical thermodynamicsThe terms statistical mechanics and statistical thermodynamics are used interchangeably...
applied to problems in physics and chemistry, especially to the structure of matter – gases, liquids, and solids.
After the War, Herzfeld returned to the University of Vienna, however, the University was in such dire financial straits that he moved to Munich in 1919, with the intent of studying analytical chemistry and getting a job in the German chemical industry, which had a highly respected reputation. First, he was an assistant at the physico-chemical laboratory of Kasimir Fajans at Ludwig Maximilians University of Munich
Ludwig Maximilians University of Munich
The Ludwig Maximilian University of Munich , commonly known as the University of Munich or LMU, is a university in Munich, Germany...
(LMU). However, once there, he found the challenge of theoretical physics more to his liking. He became Privatdozent
Privatdozent
Privatdozent or Private lecturer is a title conferred in some European university systems, especially in German-speaking countries, for someone who pursues an academic career and holds all formal qualifications to become a tenured university professor...
for theoretical physics and physical chemistry at LMU, and therefore was much more associated with Arnold Sommerfeld
Arnold Sommerfeld
Arnold Johannes Wilhelm Sommerfeld was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and groomed a large number of students for the new era of theoretical physics...
, who was ordinarius professor for theoretical physics and Director of the Institute for Theoretical Physics – a prominent organization for the study of atomic and molecular structure. From 1925, until he left LMU in 1926, he was extraordinarius professor of theoretical physics. During this time, Linus Pauling
Linus Pauling
Linus Carl Pauling was an American chemist, biochemist, peace activist, author, and educator. He was one of the most influential chemists in history and ranks among the most important scientists of the 20th century...
did postdoctoral studies with him, and he was the thesis advisor for Walter Heitler
Walter Heitler
Walter Heinrich Heitler was a German physicist who made contributions to quantum electrodynamics and quantum field theory...
, who got his doctorate in 1926. In 1925, Herzfeld published his book on kinetic theory and statistical mechanics, which became a graduate-level textbook in German-speaking universities.
Career
It was in 1926 that Herzfeld took a visiting professorship at the Johns Hopkins UniversityJohns Hopkins University
The Johns Hopkins University, commonly referred to as Johns Hopkins, JHU, or simply Hopkins, is a private research university based in Baltimore, Maryland, United States...
in Baltimore
Baltimore
Baltimore is the largest independent city in the United States and the largest city and cultural center of the US state of Maryland. The city is located in central Maryland along the tidal portion of the Patapsco River, an arm of the Chesapeake Bay. Baltimore is sometimes referred to as Baltimore...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, which developed into a regular faculty position. During 1930 and 1932, he was a lecturer at Cooper Union
Cooper Union
The Cooper Union for the Advancement of Science and Art, commonly referred to simply as Cooper Union, is a privately funded college in the East Village neighborhood of Manhattan, New York City, United States, located at Cooper Square and Astor Place...
and Fordham University
Fordham University
Fordham University is a private, nonprofit, coeducational research university in the United States, with three campuses in and around New York City. It was founded by the Roman Catholic Diocese of New York in 1841 as St...
in New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
.
While at Johns Hopkins, Herzfeld did considerable research with the chemist Francis O. Rice, who joined the University as an associate professor the same year Herzfeld arrived. Their 1928 paper considered the role of molecular vibrations in the transfer of energy between ultrasonic waves and gas molecules. At Johns Hopkins, Herzfeld worked with other European colleagues on the University’s physics faculty, namely James Franck
James Franck
James Franck was a German Jewish physicist and Nobel laureate.-Biography:Franck was born to Jacob Franck and Rebecca Nachum Drucker. Franck completed his Ph.D...
and Maria Goeppert-Mayer, who were awarded Nobel Prizes in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...
in 1925 and 1963, respectively. Franck came to Johns Hopkins after he left Germany in 1933, where he had been ordinarius professor of experimental physics and Director of the Second Institute for Experimental Physics at the University of Göttingen and a close colleague of Max Born
Max Born
Max Born was a German-born physicist and mathematician who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics and supervised the work of a number of notable physicists in the 1920s and 30s...
, who was Director of the Institute of Theoretical Physics at Göttingen. Goeppert-Mayer was a student of Born, and she joined the Johns Hopkins faculty in 1931. Goeppert-Mayer and Herzfeld published articles on states of aggregation and nuclear fusion reactions. Herzfeld coauthored articles with Franck on photosynthesis, one being after they had both left Johns Hopkins. John Archibald Wheeler
John Archibald Wheeler
John Archibald Wheeler was an American theoretical physicist who was largely responsible for reviving interest in general relativity in the United States after World War II. Wheeler also worked with Niels Bohr in explaining the basic principles behind nuclear fission...
, who became a prominent physicist, took his PhD under Herzfeld in 1933.
In 1936, Herzfeld moved to The Catholic University of America
The Catholic University of America
The Catholic University of America is a private university located in Washington, D.C. in the United States. It is a pontifical university of the Catholic Church in the United States and the only institution of higher education founded by the U.S. Catholic bishops...
in Washington, DC, where he remained until his death in 1978. He received emeritus
Emeritus
Emeritus is a post-positive adjective that is used to designate a retired professor, bishop, or other professional or as a title. The female equivalent emerita is also sometimes used.-History:...
status in 1969 and stayed active for the rest of his life.
Reasons for Herzfeld leaving Johns Hopkins were described in a letter to Arnold Sommerfeld. A main reason was the dire financial situation at Johns Hopkins. However, there were other reasons as well. One being his relationship with R. W. Wood, a professor of experimental physics and chairman of the physics department, had deteriorated. Also, J. A. Bearden, another experimentalist, thought there was too much emphasis on theoretical physics and the number of German physicists in the small department was out of balance. Bearden also suspected that Herzfeld had brought Franck to Johns Hopkins to further Herzfeld’s ambitions to be department chairman. Finally too, Bearden thought Herzfeld had caused dissension in the department over his strong support to promote Göppert-Mayer from research associate in physics to a regular faculty appointment. While Herzfeld did receive offers from both Fordham University and Catholic University, neither was appealing as they did not have strong research departments. While talking the situation over with Isaiah Bowman
Isaiah Bowman
Isaiah Bowman, AB, Ph. D. was an American geographer...
, president of Johns Hopkins, it became clear that the financial difficulties at Johns Hopkins might require downsizing the physics faculty. With this in mind, Herzfeld accepted the offer from Catholic University. Herzfeld’s teaching responsibilities and salary at Catholic University were about the same as that at Johns Hopkins, but there were additional administrative duties, as he was also chairman of the physics department.
In 1938, Herzfeld married Regina Flannery, who was an instructor at Catholic University; by the time she retired in 1970, she had risen to professor and head of that department.
In the late 1940s, Herzfeld increased the attention at Catholic University to quantum-mechanical calculations on the electronic structure of polyatomic molecules, thus establishing a respected position for the University in this field.
In 1959, Herzfeld and Theodore A. Litovitz collaborated on a book, in part, summarizing Herzfeld’s thinking on ultrasonics over the 30 plus years since his article with F. O. Rice. In 1966, Herzfeld published a review article summarizing 50 years of developments in physical ultrasonics.
Honors
- 1958 – Elected to the American Academy of Arts and SciencesAmerican Academy of Arts and SciencesThe American Academy of Arts and Sciences is an independent policy research center that conducts multidisciplinary studies of complex and emerging problems. The Academy’s elected members are leaders in the academic disciplines, the arts, business, and public affairs.James Bowdoin, John Adams, and...
- 1960 – Elected to the National Academy of SciencesUnited States National Academy of SciencesThe National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
- 1964 – US Navy’s Meritorious Service Citation for his services during World War IIWorld War IIWorld War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
Selected Literature
- Karl F. Herzfeld Über ein Atommodell, das die Balmer'sche Wasserstoffserie aussendet, Sitzungsberichte der Koniglichen Akademie der Wissenschaften Wien 121(2a):593-601 (1912)
- Karl F. Herzfeld Zur Elektronentheorie der Metalle, Annalen der Physik (4) 41:27-52 [Herzfeld's doctoral dissertation at Vienna University under the direction of Professor Friedrich Hasenöhrl] (1913)
- Karl F. Herzfeld and F. O. Rice Dispersion and absorption of high-frequency sound waves, Physical Review 31:691-95 (1928)
- Karl F. Herzfeld and Maria Goeppert-Mayer On the states of aggregation, Journal of Chemical Physics 2:38-45 (1934)
- Karl F. Herzfeld and M. Göppert-Mayer On the theory of fusion, Phys. Rev. 46:995-1001 (1935)
- Karl F. Herzfeld and James FranckJames FranckJames Franck was a German Jewish physicist and Nobel laureate.-Biography:Franck was born to Jacob Franck and Rebecca Nachum Drucker. Franck completed his Ph.D...
An attempted theory of photosynthesis, J. Chem. Phys. 5:237-51 (1937)
- Karl F. Herzfeld and James Franck Contributions to a theory of photosynthesis, J. Phys. Chem. 45:978-1025 (1941)
- Karl F. Herzfeld Electron levels in polyatomic molecules having resonating double bonds, Chemical Reviews 41:233-56 (1947)
- Karl F. Herzfeld Nodal surfaces in molecular wave functions Review of Modern Physics 21:527-30 (1949)
- Karl F. Herzfeld Fifty Years of Physical Ultrasonics, The Journal of the Acoustical Society of America Volume 39, Issue 5A, pp. 813-825, The Catholic University of America, Washington, D. C. (Received 27 July 1965)
Books
- Karl F. Herzfeld Zur Elektronentheorie der Metalle (Barth, 1913)
- Karl F. Herzfeld Physikalische und Elektrochemie In Encyklopädie der Mathematischen Wissenschften mit Einschluss ihrer AnwendungenKlein's encyclopediaIn mathematics, Klein’s encyclopedia refers to a German mathematical encyclopedia published in six volumes from 1898 to 1933. Felix Klein and Wilhelm Meyer were organizers of the encyclopedia. Its title in English is "Encyclopedia of mathematical sciences including their applications", which is...
Band V, Heft 6, pp. 947-1112 (Leipzig: B. G. Teubner, 1921)
- Karl F. Herzfeld Grösse und Bau der Moleküle In Handbuch der Physik 1st ed., band 22, ed. A. Smekal, pp. 386-519 (Berlin: Springer-Verlag, 1924) (second ed., band 24, 1933, pp. 1-252).
- Karl F. Herzrfeld, Kinetische Theorie der Wärme In Müller-Pouillets Lehrbuch der Physik Band 3 (Braunsweig: F. Viewig und Sohn, 1925)
- Karl F. Herzfeld Klassische Thermodynamik In Handbuch der Physik 1st ed., Band 9, pp. 1-140 (Berlin, Springer-Verlag, 1926)
- Karl F. Herzfeld and K. L. Wolf Absorption und dispersion In Handbuch der Physik 1st ed., Band 20, pp. 480-634 (Berlin: Springer-Verlag, 1928)
- Karl F. Herzfeld Gittertheorie der festen Körper In Handbuch der Experimental Physik Band 7, eds. W. Wien and F. Harms, pp. 325-422 (Leipzig: Akademische Verlagsgesellschaft, 1928)
- Karl F. Herzfeld and H. M. Smallwood The kinetic theory of gases and liquids In A Treatise on Physical Chemistry 2nd ed., vol. 1, ed. H. S. Taylor, pp. 73-217 (New York: Van Nostrand, 1931)
- Karl F. Herzfeld and H. M. Smallwood Imperfect gases and the liquid state In A Treatise on Physical Chemistry 2nd ed., vol. 1, ed. H. S. Taylor, pp. 219-250 (New York: Van Nostrand, 1931)
- Karl F. Herzfeld Relaxation phenomena in gases In Thermodynamics and Physics of Matter vol. 1, ed. F. Rossini, pp. 646-735 (Princeton, N.J.: Princeton University Press, 1955)
- Karl F. Herzfeld and V. Griffing Fundamental physics of gases In Thermodynamics and Physics of Matter vol. 1, ed. F. Rossini, pp. 111-176 (Princeton, N.J.: Princeton University Press, 1955)
- Karl F. Herzfeld and Theodore A. Litovitz Absorption and Dispersion of Ultrasonic Waves. Pure and Applied Physics Volume 7, (Academic Press, 1959)
- Karl F. Herzfeld Fundamental Physics of Gases (Princeton University Press, 1961)
- Karl F. Herzfeld Questions in Statistical Mechanics: Some Reactionary Viewpoints by Karl F Herzfeld (Center for Theoretical Studies, University of Miami, 1971)
External links
- Karl Herzfeld - Biographical Memoir
- Herzfeld archives - Catholic University