Fluctuating Asymmetry in Morphological Characteristics of Betula Pendula Roth Leaf under Conditions of Urban Ecosystems: Evaluation of the Multi-Factor Negative Impact. - Elena Shadrina; Nina Turmukhametova; Victoria Soldatova; Yakov Vol'pert; Irina Korotchenko; Galina Pervyshina (Symmetry, 2020)