@article {16354, title = {Model-checking concurrent systems with unbounded integer variables: symbolic representations, approximations, and experimental results}, journal = {ACM Transactions on Programming Languages and SystemsACM Trans. Program. Lang. Syst.}, volume = {21}, year = {1999}, month = {1999/07//}, pages = {747 - 789}, isbn = {01640925}, doi = {10.1145/325478.325480}, url = {http://dl.acm.org/citation.cfm?id=325480}, author = {Bultan,Tevfik and Gerber,Richard and Pugh, William} }