Researchr is a web site for finding, collecting, sharing, and reviewing scientific publications, for researchers by researchers.
Sign up for an account to create a profile with publication list, tag and review your related work, and share bibliographies with your co-authors.
Atsushi Ohta, Kohkichi Tsuji. Insufficiently marked siphon of Petri nets - extension of token-free siphon. In ISCAS (3). pages 244-247, 2003. [doi]
Abstract is missing.