BAGEMIHL, Frederick. Congruous and incongruous one-to-one correspondences. Mathematica Scandinavica, Berkeley, CA, United States, v. 1, p. 256–260, 1953. DOI: 10.7146/math.scand.a-10383. Disponível em: https://journals.msp.org/mscand/article/view/2940. Acesso em: 26 aug. 2026.