APA (7th ed.) Citation

(1971). Area handbook for ElSalvador: Research and writing were completed on Oct. 19, 1970. US Gov. Print. Off.

Chicago Style (17th ed.) Citation

Area Handbook for ElSalvador: Research and Writing Were Completed on Oct. 19, 1970. Washington, DC: US Gov. Print. Off, 1971.

MLA (9th ed.) Citation

Area Handbook for ElSalvador: Research and Writing Were Completed on Oct. 19, 1970. US Gov. Print. Off, 1971.