Affiliation: | [1]Rural Federal University of Pernambuco, Garanhuns 55292-270, Brazil; [2]Department of Statistics and Mathematics, Federal University of Acre, Rio Branco 69920-900, Brazil; [3]UNIPETECH, UNIPE, JoSo Pessoa 58053-000, Brazil; [4]Information Systems Course, Paralso College of Ceara, Juazeiro do Norte 63010-220, Brazil; [5]Federal University of Pernambuco, Recife 50670-901, Brazil |