APA-referens (7:e uppl.)

National Planning Association. (1965). The economies of fifteen metropolitan areas: A historical and projected employment output, population and personal income 1950, 1957, 1960, 1962 and 1975. [National Planning Association].

Chicago-referens (17:e uppl.)

National Planning Association. The Economies of Fifteen Metropolitan Areas: A Historical and Projected Employment Output, Population and Personal Income 1950, 1957, 1960, 1962 and 1975. Washington, D.C: [National Planning Association], 1965.

MLA-referens (9:e uppl.)

National Planning Association. The Economies of Fifteen Metropolitan Areas: A Historical and Projected Employment Output, Population and Personal Income 1950, 1957, 1960, 1962 and 1975. [National Planning Association], 1965.