Bradfield, P., Jones, M., Fosbery, R., Gregory, J., Taylor, D., & Adds, J. (2014). Cambridge International AS and A Level Biology: Teacher's Resource [ (4th ed.). Cambridge: Cambridge University Press.

Bradfield, Phil, Mary Jones, Richard Fosbery, Jennifer Gregory, Dennis Taylor, and John Adds. Cambridge International AS and A Level Biology: Teacher's Resource [. 4th ed. Cambridge: Cambridge University Press, 2014.

Bradfield, Phil, et al. Cambridge International AS and A Level Biology: Teacher's Resource [. 4th ed. Cambridge: Cambridge University Press, 2014.