SPECIAL VOLUME IN HONOUR OF RENE GUITART ON THE OCCASION OF HIS 65th BIRTHDAY This year Rene Guitart will celebrate his 65th birthday. As announced in a recent message by Andree Ehresmann, a "Journee Guitart" will take place at the Universite Paris Diderot on November 9 to celebrate his contributions in mathematics and logic. We are glad to announce that there will be a Special Volume of the "Cahiers de Topologie et Geometrie Differentielle Categoriques" dedicated to Rene Guitart. Submission of papers on the many areas in which Rene has worked is particularly encouraged. The deadline for submission for this special volume is 30 April 2013. Please send your submission to Marino Gran ( marino.gran@uclouvain.be ) as an appended PDF file: if you wish, you may suggest one of the (guest) Editors Andree Ehresmann Jean Benabou Marino Gran George Janelidze Robert Pare to handle your article. Please be sure that you receive an e-mail acknowledging the receipt of your submission. All papers will be carefully refereed following the standards of the journal "Cahiers de Topologie et Geometrie Differentielle Categoriques". With our best regards, Andree, Bob, George, Jean, and Marino [For admin and other information see: http://www.mta.ca/~cat-dist/ ]