A.I. Barros. Discrete and fractional programming technique for location models (Combinatorial Optimization; 3). Dordrecht: Kluwer, 1998. 178 p., prijs NLG 180,– ISBN 0-7923-5002-2
Aardal, K.I.
(2001) Nieuw archief voor wiskunde. Serie 5, volume 2, issue 2, pp. 85 - 85