E. Best, J. Desel, and J. Esparza. Traps characterise home states in free choice systems. Theoretical Computer Science, 101:161–176, 1992.	PDF (1 MB) Info Conference version
J. Esparza and M. Silva. A polynomial time algorithm to decide liveness of bounded free choice nets. Theoretical Computer Science, 102:185–205, 1992.	PDF (1 MB) Info
J. Esparza. A solution to the covering problem for 1-bounded conflict-free petri nets using linear programming. Information Processing Letters, 41:313–319, 1992.	PDF (947 kB) Info