Aubrey, H. G., & Darmstadter, J. (1961). Introduct: Economic challenge and response. National Planning Association.
Lua i Stíl Chicago (17ú heag.)Aubrey, Henry G., agus Joel Darmstadter. Introduct: Economic Challenge and Response. Washington: National Planning Association, 1961.
Lua MLA (9ú heag.)Aubrey, Henry G., agus Joel Darmstadter. Introduct: Economic Challenge and Response. National Planning Association, 1961.
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