REYNA, J. L. Hubert M. Blalock Jr. Causal inferences in non-experimental research. Chapel Hill, [N. C.] : The University of North Carolina Press, 1964. ix, 200 p. Estudios Demográficos y Urbanos, [S. l.], v. 3, n. 03, p. 384–385, 1969. DOI: 10.24201/edu.v3i03.87. Disponível em: https://estudiosdemograficosyurbanos.colmex.mx/index.php/edu/article/view/87. Acesso em: 26 abr. 2024.