1.
Biggs N. Discrete Mathematics. Rev. ed. Clarendon; 1989.
2.
Grimaldi RP. Discrete and Combinatorial Mathematics: An Applied Introduction. Fifth edition. Pearson Education Limited; 2014. https://www.vlebooks.com/vleweb/product/openreader?id=AberystUni&isbn=9781292035994
3.
Liu CL. Elements of Discrete Mathematics. Vol McGraw-Hill computer science series. 2nd ed. McGraw-Hill; 1985.
4.
Wilson RJ, Watkins JJ. Graphs: An Introductory Approach: A First Course in Discrete Mathematics. Wiley; 1990.