National Research Council. Panel on Collection. (1981). Collecting data for the estimation of fertility and mortality. National Academy Press.
Dyfyniad Arddull ChicagoNational Research Council. Panel on Collection. Collecting Data for the Estimation of Fertility and Mortality. Washington: National Academy Press, 1981.
Dyfyniad MLANational Research Council. Panel on Collection. Collecting Data for the Estimation of Fertility and Mortality. National Academy Press, 1981.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.