APA (7th ed.) Citation

ScienceDirect (Online service), Hirs, C. H. W., & Timasheff, S. N. (1978). Enzyme structure. Academic Press.

Chicago Style (17th ed.) Citation

ScienceDirect (Online service), C. H. W. Hirs, and Serge N. Timasheff. Enzyme Structure. New York: Academic Press, 1978.

MLA (9th ed.) Citation

ScienceDirect (Online service), et al. Enzyme Structure. Academic Press, 1978.