http://www.verisity.com/products/specman.html

http://www.cl.cam.ac.uk/~mjcg/Sugar/

http://www.alphaworks.ibm.com/tech/FoCs

http://www.cl.cam.ac.uk/research/srg/han/hprls/orangepath/transactors

http://www.open-vera.com/

http://en.wikipedia.org/wiki/Formal_equivalence_checking

http://www.project-veripage.com/psl_tutorial_2.php

http://baldur.iti.uka.de/sat-race-2008/index.html

http://www.te.rl.ac.uk/europractice/vendors/formality_ds.pdf