Rubtsov, I.A. 1952 On the direction of variability in connection with host specialization in willow hard-scale [Chionaspis salicis L.]. Zoologicheskii Zhurnal. Moscow 31: 179-182.
Rubtsov, I.A. 1952 On the direction of variability in connection with host specialization in willow hard-scale [Chionaspis salicis L.]. Zoologicheskii Zhurnal. Moscow 31: 179-182.