Croft, T. and Davison, R. (2010a) Foundation maths. 5th ed. Harlow: Prentice Hall. Available at: http://www.vlebooks.com/vleweb/product/openreader?id=AberystUni&isbn=9780273729488.
Croft, T. and Davison, R. (2010b) Foundation maths. 5th ed. Harlow: Pearson/Prentice Hall.
Rosen, K.H. and Krithivasan, K. (2013) Discrete mathematics and its applications. 7th ed., Global ed. New York: McGraw-Hill.