References

For Tulipa

Straley, G.B., and F.H. Utech. 2002a. Tulipa. In Flora of North America Editorial Committee. 2002a. Flora of North America north of Mexico. Volume 26, Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York, NY. 723 pp. Google Scholar

Tamura, M.N. 1998b. Liliaceae. Pp. 343-353. In Kubitzki, K., ed. 1998a. The families and genera of vascular plants. III. Flowering plants – Monocotyledons – Lilianae (except Orchidaceae). Springer, Berlin. 478 pp. Google Scholar