Relational and algebraic methods in computer science [Electronic resource] : 12th international conference, RAMICS 2011, Rotterdam, the Netherlands, May 30 – June 3, 2011 : proceedings / ed. H. Swart. - Electronic text data. - Berlin ; Heidelberg : Springer, 2011. - (Lecture notes in computer science, ISSN 0302-9743 ; 6663). - ISBN 978-3-642-21070-9 : Б. ц.