United States. National Capital Regional Planning Council. (1966). The regional development guide, 1966-2000. U.S. Govt. Print Off.
Chicago-viite (17. p.)United States. National Capital Regional Planning Council. The Regional Development Guide, 1966-2000. Washington,D. C: U.S. Govt. Print Off, 1966.
MLA-viite (9. p.)United States. National Capital Regional Planning Council. The Regional Development Guide, 1966-2000. U.S. Govt. Print Off, 1966.
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