APA (7th ed.) Citation

Bulmer, Schwerzel, & Sykes. (1993). Directory of social research organisations in the United Kingdom. Mansell.

Chicago Style (17th ed.) Citation

Bulmer, Schwerzel, and Sykes. Directory of Social Research Organisations in the United Kingdom. London, England New York, N.Y., USA: Mansell, 1993.

MLA (9th ed.) Citation

Bulmer, et al. Directory of Social Research Organisations in the United Kingdom. Mansell, 1993.