Verbatim text: Tryon, A. F. 1949. Spores of the genus Selaginella in North America, north of Mexico. Ann. Missouri Bot. Gard. 36: 413--431.
Author: Tryon, A.F.
Year: 1949
Title: Spores of the genus Selaginella in North America, north of Mexico
Journal: Ann. Missouri Bot. Gard
Volume: 36
Pages: 413–431
BHL link: http://www.biodiversitylibrary.org/part/26888