Bongaarts, John The proximate determinants of natural marital fertility / John Bongaarts - New York : Population Council (PC) , 1982 - 44p. : ill. ; 22 cm. - Working papers (Population Council. Center for Policy Studies) No. 89 . Includes bibliographical references. Subjects--Topical Terms: Fertility, HumanBirth intervals Gov. Doc. Class. No.: US PC CPS WP-89