Reference: Ahmed Bouajjani, Javier Esparza, and Tayssir Touili. Reachability analysis of synchronized PA-systems. Electronic Notes in Theoretical Computer Science, 138(3):153–178, 2005. Suggested BibTeX entry: @article{BET05,     author = {Ahmed Bouajjani and Javier Esparza and Tayssir Touili},     journal = {Electronic Notes in Theoretical Computer Science},     number = {3},     pages = {153--178},     title = {Reachability Analysis of Synchronized {PA}-Systems},     volume = {138},     year = {2005} }

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