2007 · Hildebrand, M, Ossenbruggen, JR van, et al. · Centrum Wiskunde & Informatica (CWI), the national research institute for mathematics and computer science in the Netherlands · 19
2004 · MJ Alberink, LW Rutledge, et al. · Centrum Wiskunde & Informatica (CWI), the national research institute for mathematics and computer science in the Netherlands · 6
2006 · Željko Obrenović, F.M. Nack, et al. · Centrum Wiskunde & Informatica (CWI), the national research institute for mathematics and computer science in the Netherlands · 3