APA (7th ed.) Citation

Gray, J. H. (1970). Biological science: Organisms and population, a laboratory guide. Penguin Books.

Chicago Style (17th ed.) Citation

Gray, John H. Biological Science: Organisms and Population, a Laboratory Guide. Harmondsworth, England, United Kingdom: Penguin Books, 1970.

MLA (9th ed.) Citation

Gray, John H. Biological Science: Organisms and Population, a Laboratory Guide. Penguin Books, 1970.