APA

United States, . (1992). Environmental quality: annual report. Washington: U.S. Govt. Print Off.

Chicago

United States, . 1992. Environmental quality: annual report. Washington: U.S. Govt. Print Off.

Harvard

United States, . (1992). Environmental quality: annual report. Washington: U.S. Govt. Print Off.

MLA

United States, . Environmental quality: annual report. Washington: U.S. Govt. Print Off. 1992.