APA (7th ed.) Citation

Briggs, A., Isaacs, A., & Martin, E. A. (1985). Longman dictionary of 20th century biography. Longman.

Chicago Style (17th ed.) Citation

Briggs, Asa, Alan Isaacs, and E. A. Martin. Longman Dictionary of 20th Century Biography. Harlow: Longman, 1985.

MLA (9th ed.) Citation

Briggs, Asa, et al. Longman Dictionary of 20th Century Biography. Longman, 1985.