APA (7th ed.) Citation

Roget, P. M., & Kirkpatrick, B. (1998). Roget's thesaurus (1998 ed.). Penguin Books.

Chicago Style (17th ed.) Citation

Roget, Peter Mark, and Betty Kirkpatrick. Roget's Thesaurus. 1998 ed. London, UK: Penguin Books, 1998.

MLA (9th ed.) Citation

Roget, Peter Mark, and Betty Kirkpatrick. Roget's Thesaurus. 1998 ed. Penguin Books, 1998.

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