Lerner, S. 1971. International Union For the Scientific Study of Population. International Population Conference, London, 1969. Lieja, 1971. 4 v., 3050 p. Estudios Demográficos y Urbanos. 5, 02 (may 1971), 244–245. DOI:https://doi.org/10.24201/edu.v5i02.132.