References
Pryer, K.M. 1992. The status of Gymnocarpium heterosporum and G. robertianum in Pennsylvania. Amer. Fern J. 82: 34-39. Google Scholar
Pryer, K.M. 1992. The status of Gymnocarpium heterosporum and G. robertianum in Pennsylvania. Amer. Fern J. 82: 34-39. Google Scholar