Bamford, C., Brunskill, K., Cain, G., Grant, C., Munday, S., & Walthon, S. (2002). Economics: AS level and A level. New York: Cambridge University Press.

Bamford, Colin, Keith Brunskill, Gordon Cain, Cue Grant, Stephen Munday, and Stephen Walthon. Economics: AS Level and A Level. New York: Cambridge University Press, 2002.

Bamford, Colin, et al. Economics: AS Level and A Level. New York: Cambridge University Press, 2002.