References
- Wright . Palæont. Soc. Publ. , xxiv 144 – 144 .
- Tate . Quart. Journ. Geol. Soc. , xxxiii 256 – 256 .
- Agassiz , A. 1872 . Echini of the Eastern Coast of the United States . Illust. Cat. Harvard Coll. , : 261 – 261 . no. vii.Lovén, “Études sur les Echinoïdes” Kongl. Svenska Vetenskaps-Akad. Handlingar, Bd. II. no. 7, p. 27.