Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 244, part 1
Inferring Stratigraphic Position of Fossil Vertebrates from the Niobrara Chalk of western Kansas--Fig. 4

Fig. 4. Inferred stratigraphic positions or ranges of type and other important specimens of Pteranodon plotted against the composite stratigraphic column from Hattin (1982). Marker units are indicated by black lines or bands, or in the case of Marker Unit 10, the prominent caprock, by cross-hatching. Institutional abbreviations: AMNH, American Museum of Natural History, New York; DMNH, Denver Museum of Natural History; KUVP, Natural History Museum, University of Kansas, Lawrence; LACM, Los Angeles County Museum of Natural History; UALVP, Geology Museum, University of Alberta, Edmonton; "UNC", Uncatalogued specimen (see Bennett, 1991); USNM, U.S. National Museum, Washington, D.C; UUPI, Palaeontological Institute, University of Uppsala, Uppsala, Sweden; YPM, Yale Peabody Museum, New Haven.