Khapugin, Anatoliy A. “Seed Mass and Aeed Yield of Six Roses (Rosa L., Rosacear Adans.) from C Entral Russia (Republic of Mordovia)”. Plant Breeding and Seed Science, vol. 71, June 2015, pp. 13-22, http://ojs.ihar.edu.pl/index.php/pbss/article/view/259.