Margrain, E., Margrain, R., Robinson, A., & Stevenson, J. (1988). GCSE biology questions: E. Margrain, R. Margrain, A. Robinson, J. Stevenson. Blackie.
Citazione stile Chigago Style (17a edizione)Margrain, Elza, R. Margrain, A. Robinson, e J. Stevenson. GCSE Biology Questions: E. Margrain, R. Margrain, A. Robinson, J. Stevenson. London: Blackie, 1988.
Citatione MLA (9a ed.)Margrain, Elza, et al. GCSE Biology Questions: E. Margrain, R. Margrain, A. Robinson, J. Stevenson. Blackie, 1988.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.