APA (7th ed.) Citation

Earl, B., Saunders, A., & Wilford, L. (1989). GCSE chemistry assessment. Blackie.

Chicago Style (17th ed.) Citation

Earl, B., A. Saunders, and L.D.R Wilford. GCSE Chemistry Assessment. London: Blackie, 1989.

MLA (9th ed.) Citation

Earl, B., et al. GCSE Chemistry Assessment. Blackie, 1989.