1. Upper Carboniferous anaptychi from Uruguay;Closs;Ameghiniana,1967
2. Goniatiten mit Radula und Kieferapparat in der Itarare–Formation von Uruguay;Closs;PalHont. Z.,1967
3. Morfologiya i funktsionl' noye znacheniye an aptikhor;Dagys;Paleont. Zhur. 1975,1975
4. Historic Pennsylvanian ammonoids from Iowa;Furnish;Iowa Acad. Sci. Proc.,1966
5. Gordon, M. Jr. 1971. Primitive squid gladii from the Permian of Utah. U. S. Geol. Surv. Prof. Paper 750-c, p. 34-38.