References
Struwe, L., J.W. Kadereit, J. Klackenberg, S. Nilsson, M. Thiv, B. von Hagen, and V.A. Albert. 2002. Systematics, character evolution, and biogeography of Gentianaceae, including a new tribal and tribal classification. In Struwe, L., and V.A. Albert, eds. 2002. Gentianaceae: systematics and natural history. Cambridge Univ. Press, Cambridge. 652 pp. Google Scholar