References in English

• James Hein. Discrete Structures, Logic and computability, Jones and Bartlett.  (study guide) [JH_GUIDE]

Half-open access.

• Gordon J. Pace. Mathematics of Discrete Structures for Computer Science, Springer, 2012. [GP_MDSCS]

Wikibook.

• Discrete Mathematics, Wikibook. [WBOOK]
  

Further online readings.

• Vlalden Koltun. Discrete Structures, Lecture Notes, Stanford, 2008. [VK_DSLN]
• Rafael Pass, Wei-Lung Dustin Tseng. A Course in Discrete Structures, Cornell. [RP_CDS]
• Ken Bogart, Scot Drysdale, Cliff Stein. Discrete Math for Computer Science Students, 2004 [KB_DMCSS]