Kostikova, V.A., A.A. Kuznetsov, V.I. Troshkina, and A.P. Belanova. “Morphological and Taxonomic Analysis of the Polymorphic Complex Spiraea Betulifolia ‒ Spiraea Beauverdiana in Russia”. Acta Biologica Sibirica 5, no. 3 (September 6, 2019): 22-32. Accessed November 12, 2019. http://journal.asu.ru/biol/article/view/6353.