| 
Miller & Garner | 
1955 | 
Lower Mississippian cephalopods of Michigan. Part III. Ammonoids and summary.	 
Contributions, Museum of Paleontology. Univ. Michigan, 12: 113-173, fig.1-16, pl.1-7; Michigan.	 
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 | 
Weyer | 
1972 | 
Zum Alter der Ammonoideen-Faunen des Marshall-Sandsteins (Unterkarbon; Michigan, USA).	 
Berichte der deutschen Gesellschaft der geologischen Wissenschaften, A, Geol. Paläont., 17 (3): 325-350, 1 fig., 1 tab.; Berlin.	 
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