W. Bruyn, R. Jensen, D. Keskar & P. Ward (1988):
An Extended Systems Modeling Language Based on the Data Flow Diagram.
ACM SIGSOFT Software Engineering Notes 13(1),
pp. 58–67,
doi:10.1145/43857.43866.
B. DeVries (2013):
Mapping of UML Diagrams to Extended Petri Nets for Formal Verification.
Grand Valley State University,
Allendale, Michigan * .
Available at http://scholarworks.gvsu.edu/cistechlib/156.
D. Harel (1988):
On visual formalisms.
Communications of the ACM 31(5),
pp. 514–530,
doi:10.1145/42411.42414.
D. Harel (1998):
Private conversation at OOPSLA Conference,
Vancouver, British Columbia. Canada.
i-Logix (1990):
i-Logix technical presentation to Smiths Industries,
Grand Rapids, Michigan.
i-Logix (1991):
i-Logix training cours,
Andover, Massachusetts.
P. Jorgensen (2008):
Software testing - a craftsman's approach,
4th edition.
Taylor & Francis ISBN = "978-1-4665-6808-0",,
pp. I-XXIX, 1-464.
eptcs@eptcs.org