Urbanization: the challenge for the next century.
D003247:Conservation of Natural Resources; D003710:Demography; D004777:Environment; D005843:Geography; D006262:Health; D011153:Population; D011157:Population Dynamics; D011158:Population Growth; D011634:Public Health; D012499:Sanitation; D014505:Urban Population; D014507:Urbanization; D014881:Water Supply
Demographic Factors; Environment; Environmental Degradation; Geographic Factors; Health; Natural Resources; Population; Population Dynamics; Population Growth; Public Health; Sanitation; Spatial Distribution; Urban Spatial Distribution; Urbanization; Water Supply; World