APA (7th ed.) Citation

United States. Office of Personnel Management. (1990). Pay rates of the General Schedule, 1978-1991 (Rev. Dec. 1990.). [The Office].

Chicago Style (17th ed.) Citation

United States. Office of Personnel Management. Pay Rates of the General Schedule, 1978-1991. Rev. Dec. 1990. [Washington, D.C.?]: [The Office], 1990.

MLA (9th ed.) Citation

United States. Office of Personnel Management. Pay Rates of the General Schedule, 1978-1991. Rev. Dec. 1990. [The Office], 1990.