Underdeveloped areas -- Periodicals 3 Congresses 2 Housing 2 Economic Development -- 1 Economic developement -- 1 Economic development -- 1 more ... Housing -- 1 Mineral industries 1 Rural development -- 1 Sampling (Statistics) 1 Social conditions -- 1 Social survey 1 Underdevelop areas -- 1 Underdevelope areas -- 1 Urbanization 1 Women -- 1 cities and towns -- 1 city planning -- 1 mathematical models 1 social aspects 1 less ...