V. V. Tkach
Chernivtsi National University, Chernivtsi
Ukraine

S. C. de Oliveira
Federal University of Mato Grosso do Sul
Brazil

S. K. B. de Oliveira
Federal Rural University of Pernambuco
Brazil

R. Ojani
University of Mazandaran, Babolsar
Iran, Islamic Republic of

O. V. Elenich
Chernivtsi National University, Chernivtsi
Ukraine

P. I. Yagodynets
Chernivtsi National University, Chernivtsi
Ukraine