Further reading

• Anon. 1925 David Geyer zum 70. Geburtstage!. Archiv für Molluskenkunde, 57: 161.
• Wägele H. 1933. David Geyer Geb. 6. Nov. 1855, gest. 6. Nov. 1932. Archiv für Molluskenkunde, 65: 70-84.

External links

• Works by David Geyer at Internet Archive
  Internet Archive
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