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  3. with F. Göbel, Graceful disconnected graphs, TH Twente Report 245 (1979)
  4. On sublattices of the Leech lattice and primitive reflection groups, MC Report ZN 93 (1979)
  5. A synopsis of known distance-regular graphs with large diameters, MC Report ZW 168 (1981)
  6. with A.E. Brouwer, The Poincaré series of the polynomials invariant under SU2 in its irreducible representations of degree 17, MC Report ZW 134 (1979)
  7. with J. Brinkhuis, On the covariant theory of SL(2,C) and the Grassmann variety, Erasmus University Report (1987)
  8. Arjeh M. Cohen Tits' construction of the Ree groups, Amsterdam, Dec 1983.
  9. A.M. Cohen, H. Cuypers, K. Poels, M. Spanbroek, R. Verrijzer, WExEd - WebALT Exercise Editor for Multilingual Mathematical Exercises, contribution to the WebALT 2006 conference, January 5,6, 2006, Eindhoven.