L.W.D.van Raamsdonk 1998 - Raamsdonk LWD (1998) A new species Tulipa heweri related to T. praestans (Liliaceae). Nordic Journal of Botany 18(1): 51-56. doi: 10.1111/j.1756-1051.1998.tb01099.x.
There is no corrections for Tulipa heweri yet.