APA (7th ed.) Citation

(1971). A Directory of Information Resources in the United States: Physical Sciences, Engineering.

Chicago Style (17th ed.) Citation

A Directory of Information Resources in the United States: Physical Sciences, Engineering. 1971.

MLA (9th ed.) Citation

A Directory of Information Resources in the United States: Physical Sciences, Engineering. 1971.

Warning: These citations may not always be 100% accurate.