List of publications

1. Formulae for sums involving a reduced set of residues modulo n, Proc. Edin. Math. Soc., 13 (1963), 347-349.
2. A new class of Hadamard matrices, Glas. Math. J., 8 (1967), 59-62.
3. Packing of spheres in l_p, Glas. Math. J., 11 (1970), 72-80.
4. Some new symmetric block designs, J. Comb. Theory, 11 (1971), 299-302.
5. A note on equivalence of Hadamard matrices, Notices of the American Mathematical Society, 18:624 1971.
6. The index of a subgroup of the modular group, Mich. Math. J., 19 (1972), 57-64.
7. Hadamard Designs, Proc. Amer. Math. Soc., 32 (1972), 29-31.
8. M-symplectic matrices, Trans. Amer. Math. Soc., 170 (1972), 447-457.
9. Matrix divisors of mI, Acta. Arith., 20 (1972), 189-201.
10. The difference between consecutive members of a difference set (mod v), Proc. Amer. Math. Soc., 46 (1974), 150-154.
11. Skew Hadamard matrices of order 2(q+1), Notices of the American Mathematical Society, 23: A-303, 1975.
12. Skew Hadamard matrices of the Goethals-Seidel type, Can. J. Math., 27 (1975), 555-560.
13. With M. J. Ganley, Relative difference sets and quasiregular collineation groups, J. Comb. Theory (series A), 19 (1975) 134-153.
14. Hadamard matrices from relative differences sets, J. Comb. Theory (series A), 19 (1975), 287-300.
15. Hadamard matrices of order 2q^r(q+1) and q^r(q+1), Notices of the American Mathematical Society, 23:A-353, 1976.
16. A family of difference sets, J. Comb. Theory (series A), 22 (1977), 103-106.
17. Skew Hadamard matrices of order 2(q+1), Discrete Math. 18 (1977), 79-85.
18. An infinite family of Williamson matrices, J. Austr. Math. Soc. (series A) 24 (1977), 252-256.
19. With F.C.Bussemaker, W.H.Haemers and J.J.Seidel, On (v,k,lambda) graphs and designs with trivial automorphism group, J. Comb. Theory (series A) 50 (1989), 33-46.
20. (40,13,4) designs derived from strongly regular graphs, in: Advances in Finite Geometry and Designs, Oxford University Press, (Proc. Isle of Thorns Conference on Finite Geometry and Designs, Sussex, 1990), 359-368.
21. With W.H.Haemers, On (v,k,lambda) graphs and designs without involution, COMBINATORICS 88, Proceedings of the International Conference on Incidence Geometries and Combinatorial Structures (Ravello, Italy, 1988), 2 (1991), 437-447
22. Symmetric (31,10,3) designs with a non-trivial automorphism of odd order, Journ. of Comb. Math. and Comb. Designs 10, (1991), 51-64.
23. Eigenvalues of a class of (0,+1,-1) symmetric matrices, Lin. Alg. and its Appl.,166, (1992), 237-259.
24. A complete classification of (31,10,3)-designs, Designs, Codes and Cryptography, 2, (1992) 127-136.
25. Is Taylor's graph geometric?, Proceeding of Symposium on Discrete Mathematics, The Netherlands, Discrete Math., 106/107 (1992), 449-454.
26. With V.D.Tonchev, Extremal self-dual codes from symmetric designs, Discrete Math 110 (1992) 265-268.
27. Symmetric (41,16,6) designs with a non-trivial automorphism of odd order, J. Combin. Designs 1 (1993) 193-211.
28. With V.D.Tonchev and T.van Trung, A symmetric (164,54,18) design, J. Combin. Designs 1 (1993) 65-68.
29. A new family of symmetric 2-(v,k, lambda) block designs, Europ. J. Combinatorics 14 (1993) 131-136.
30. With C. Parker and V. D. Tonchev, Designs with the symmetric difference property on 64 points and their groups, J. Combin. Theory Ser. A 67 (1994), 23-43.
31. Classification of Hadamard Matrices of Orders 24 and 28, Discrete Math., 140 (1995) 185-243.
32. With W. H. Haemers, Graphs Co-spectral with Distance-regular Graphs, Journ. Lin. Multilinear Algebra, 39 (1995) 91-107.
33. Classification and Construction of Combinatorial Designs, in Surveys in Combinatorics, London Math. Lecture Note Series 218, Cambridge Univ. Press (1995) 191-213
34. Regular Two-Graphs on 36 Vertices, Lin.Alg. and its Appl., 226-228 (1995) 459-497
35. Five Nondual 2-(41,16,6) Designs with a Trivial Automorphism group, Ars Combin 41 (1995) 117-122.
36. With R. A. Mathon, On (45,12,3) Designs, J. Combin. Designs, 4 (1996), no. 3, 155-175.
37. "Two-Graphs", in: The CRC Handbook of Combinatorial Designs, CRC Press 1996, pp 686-694.
38. The Complete Classification of Steiner Systems S(2,4,25), Journ. Comb. Designs 4 (1996), no. 4, 295-300.
39. With Edwin R van Dam, Small Regular Graphs with Four Eigenvalues, Discrete Math. 189 (1998) 233-257.
40. All 2-(21,7,3) Designs are Residual, Bull. Belg. Math. Soc. 5 (1998), 441-445.
41. With M.-O. Pavcevic, Some new symmetric designs with \lambda = 10 having an automorphism of order 5, Discrete Math. 196 (1999), 257-266.
42. With D. de Caen and E.R. van Dam, A nonregular analogue of conference graphs, J. Comb. Theory Ser. A 88 194-204 (1999)
43. With M.-O. Pavcevic, Some new symmetric designs, J. Comb. Designs 7 (1999) 426-430
44. With F. C. Bussemaker and W. H. Haemers, The search for pseudo orthogonal Latin squares of order 6, Designs Codes and Cryptography, 21 (2000), 77-82.
45. The Strongly Regular (40,12,2,4) Graphs, Elec. Journ. Combin. Vol. 7(1), 2000.
46. With W. H. Haemers, The Pseudo-Geometric Graphs for Generalised Quadrangles of Order (3,t), European J. Combin. 22 (2001), no. 6, 839-845.
47. With Brendan McKay, The Classification of Regular Two-graphs on 36 and 38 vertices, Australas. J. Combin.. 24 (2001), 293-300.
48. With W. H. Haemers, Enumeration of cospectral graphs, European J. Combin, 25 (2004), 199-211.
49. With E. R. van Dam, Combinatorial designs with two singular values I: uniform multiplicative designs, J. Combin. Theory, Series A , 107 (2004) 127-142.
50. With E. R. Dam, Combinatorial designs with two singular values II. Partial geometric designs, Lin. Alg. and its Appl., 396 (2005) 303-316.
51. With K. Coolsaet & J. Degraer, The Strongly Regular (45,12,3,3) graphs, Elec. Journ. Combin., Vol. 13 (1) , (2006).
52. With E. R. van Dam, W. H. Haemers & J. H. Koolen, Characterizing Distance Regularity of Graphs by the Spectrum, Journ. Combin. Theory, Series A, Vol 113 (8) (2006), 1805-1820.
53. With A. E. Brouwer, Cospectral graphs on 12 vertices, Elec. Journ. Combin., Vol. 16 (20) (2009).