H. YenC. ChenHSU-CHUN YEN2018-09-102018-09-102007-06http://scholars.lib.ntu.edu.tw/handle/123456789/333642Computing Minimal Elements of Upward-Closed Sets for Petri Netsconference paper10.1007/978-3-540-73094-1_272-s2.0-38149092539