When Pfeffer's name is listed as an authority for a taxon such as the land snail genus LamellaxisStrebel & Pfeffer, 1882, his name is not simply an orthographic error for the more commonly encountered molluscan authority Pfeiffer, i.e. Ludwig Karl Georg Pfeiffer, who lived 50 years earlier, from 1805 to 1877.
Pfeffer GJ (1912). "Die Cephalopoden der Plankton-Expedition. Zugleich eine Monographische Übersicht der Oegopsiden Cephalopoden". In: Ergebnisse der Plankton-Expedition der Humboldt-Stiftung, Band 12 [Volume 12]. Kiel and Leipzig: Lipsius & Tischer.
Pfeffer GJ (1930). "Zur Kentniss tertiärer Landschnecken ". Geologische und Paleontologische Abhandlungen (new series) 17 (3): 1–230 + plates 1–3.
^Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN978-1-4214-0135-5. ("Pfeffer", p. 205).