Kennedy, William James <br/><br/>
The heteromorph ammonite Didymoceras cochleatum (Meek and Hayden, 1858), from the Pierre Shale of South Dakota and Wyoming 

 - New York  American Museum of Natural History  August 1999 
 - 8 p.  láms. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>AMMONOIDEA<br/>CRETACEO SUPERIOR
<br/><br/><label>Subjects--Geographic Terms: </label><br/>ESTADOS UNIDOS