[A task of great political importance].
D003625:Data Collection; D003710:Demography; D019049:Developed Countries; D004467:Economics; D004641:Emigration and Immigration; D005191:Family Characteristics; D006079:Government Publications as Topic; D011153:Population; D011157:Population Dynamics; D012106:Research; D012494:Sampling Studies; D012939:Social Planning; D014586:USSR
Data Collection; Demographic Factors; Demographic Surveys; Developed Countries; Development Planning; Economic Factors; Family And Household; Family Characteristics; Family Size; Five-year Plans; Government Publication; Migration; Population; Population Dynamics; Research Methodology; Sampling Studies; Studies; Survey Methodology; Surveys; Ussr