@InCollection{Korczyński:2001,
author
=
"W.Korczyński and K.Głazek",
title
=
"On some connections between Petri nets and semirings",
pages
=
"32--50",
year
=
"2001",
booktitle
=
"Algebra and model theory 3 ISBN: 5778201753",
publisher
=
"Novosibirsk State Technical University",
address
=
"Novosibirsk",
}