# North American Plesiosaurs: Elasmosaurus, Cimoliasaurus, and Polycotylus

> 1906 edition of article by Samuel Wendell Williston

**Wikidata**: [Q24067154](https://www.wikidata.org/wiki/Q24067154)  
**Source**: https://4ort.xyz/entity/north-american-plesiosaurs-elasmosaurus-cimoliasaurus-and-polycotylus