APA (7th ed.) Citation

Underwriters' Laboratories. (1977). Electrical construction materials directory. [Underwriters' Laboratories].

Chicago Style (17th ed.) Citation

Underwriters' Laboratories. Electrical Construction Materials Directory. [Chicago]: [Underwriters' Laboratories], 1977.

MLA (9th ed.) Citation

Underwriters' Laboratories. Electrical Construction Materials Directory. [Underwriters' Laboratories], 1977.

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