Verbatim text: Whitmore, S. A. and A. R. Smith. 1991. Recognition of the tetraploid, Polypodium calirhiza (Polypodiaceae), in western North America. Madroño 38: 233--248.
Author: Whitmore, S.A., Smith, A.R.
Year: 1991
Title: Recognition of the tetraploid, Polypodium calirhiza (Polypodiaceae), in western North America
Journal: Madroño
Volume: 38
Pages: 233–248