http://chettinadtech.ac.in/storage/13-07-10/13-07-10-16-11-21-2049-mkumar.pdf

https://ftp.utcluj.ro/pub/users/cemil/asm/CH02.PDF

http://www.edwardbosworth.com/My5155Textbook_PDF/MyText5155_Ch04.pdf

http://bnrg.cs.berkeley.edu/~randy/Courses/CS150.F00/CLD2/chapter02.pdf

http://www.ee.surrey.ac.uk/Projects/Labview/minimisation/karnaugh.html