H. Herre, and A. Hummel. Proceedings of the 23rd Workshop on (Constraint) Logic Programming (WLP 2009), Potsdam, Germany, September 15-16, 2009, page 81-94. Universitätsverlag Potsdam, (2009)
H. Herre, and A. Hummel. Proceedings of the 23rd Workshop on (Constraint) Logic Programming (WLP 2009), Potsdam, Germany, September 15-16, 2009, page 95–108. Universitätsverlag Potsdam, (2009)