Modal-Like Operators in Boolean Lattices, Galois Connections and Fixed Points.

Jouni Järvinen Michiro Kondo Jari Kortelainen Modal-Like Operators in Boolean Lattices, Galois Connections and Fixed Points. 129-145 2007 76 Fundam. Inform. 1-2 http://iospress.metapress.com/openurl.asp?genre=article&issn=0169-2968&volume=76&issue=1&spage=129 db/journals/fuin/fuin76.html#JarvinenKK07