References
For Botrypus
Hauk, W.D., C.R. Parks, and M.W. Chase. 2003. Phylogenetic studies of Ophioglossaceae: evidence from rbcL and trnL-F plastid DNA sequences and morphology. Molec. Phylogen. Evol. 28: 131-151. Google Scholar
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Zhang & Sahashi. 2013. In FoC. Google Scholar
Zhang, L., X.‐P. Fan, S. Petchsri, L. Zhou, R. Pollawatn, X. Zhang, X.‐M. Zhou, N.T. Lu, R. Knapp, S. Chantanaorrapint, P. Limpanasittichai, H. Sun, X.‐F. Gao, and L.‐B. Zhang. 2020. Evolutionary relationships of the ancient fern lineage the adder's tongues (Ophioglossaceae) with description of Sahashia gen. nov. Cladistics 36: 380-393. Google Scholar