APA (7e ed.) Bronvermelding

Clarke, L. H., & Norton, F. G. J. (1984). Ordinary Level mathematics (7th ed.(revised).). Heinemann Educational.

Chicago (17e ed.) Bronvermelding

Clarke, L. Harwood, en F. G. J. Norton. Ordinary Level Mathematics. 7th ed.(revised). London: Heinemann Educational, 1984.

MLA (8e ed.) Bronvermelding

Clarke, L. Harwood, en F. G. J. Norton. Ordinary Level Mathematics. 7th ed.(revised). Heinemann Educational, 1984.