Spengler, Joseph J ed. Population theory and policy : selected readings / edited by Joseph J Spengler and Otis Dudley Duncan - Glencoe : Free Press, 1956. - x, 522p. : diagrs., tables. Bibliography: p. 510-519. ISBN: 0136871526 0136871453 Subjects--Topical Terms: Population. Dewey Class. No.: 304.60 / SPE/P