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Carmen Popescu
“Vasile Alecsandri” University of Bacău, Department of Mathematics, Informatics and Educational Sciences, Calea Mărăşeşti 157, Bacău, RO-600115, Romania
Dorel Ureche
“Vasile Alecsandri” University of Bacău, Department of Biology and Environmental Protection, Calea Mărăşeşti 157, Bacău, RO-600115, Romania
Camelia Ureche
“Vasile Alecsandri” University of Bacău, Department of Biology and Environmental Protection, Calea Mărăşeşti 157, Bacău, RO-600115, Romania
Elena Nechita
“Vasile Alecsandri” University of Bacău, Department of Mathematics, Informatics and Educational Sciences, Calea Mărăşeşti 157, Bacău, RO-600115, Romania