On Some Problems of Lovász Concerning the Shannon Capacity of a Graph. - Willem H. Haemers (IEEE Trans. Inf. Theory, 1979)

A Contribution to the Techniques of Traffic Engineering in Communications Networks With Waiting Facilities. - B. Sanders; Willem H. Haemers; R. Wilcke (ICC (1), 1984)

Access Control at the Netherlands Postal and Telecommunications Services. - Willem H. Haemers (CRYPTO, 1985)

A (49, 16, 3, 6) Strongly Regular Graph Does Not Exist. - Frans C. Bussemaker; Willem H. Haemers; R. Matron; Henny A. Wilbrink (Eur. J. Comb., 1989)

On (v, k, lambda) graphs and designs with trivial automorphism group. - Frans C. Bussemaker; Willem H. Haemers; J. J. Seidel; Edward Spence (J. Comb. Theory A, 1989)

Regular 2-Graphs and Extensions of Partial Geometries. - Willem H. Haemers (Eur. J. Comb., 1991)

Divisible designs with r-lambda1 = 1. - Willem H. Haemers (J. Comb. Theory A, 1991)

Structure and uniqueness of the (81, 20, 1, 6) strongly regular graph. - Andries E. Brouwer; Willem H. Haemers (Discret. Math., 1992)

Some 2-ranks. - Andries E. Brouwer; Henny A. Wilbrink; Willem H. Haemers (Discret. Math., 1992)

The Gewirtz Graph: An Exercise in the Theory of Graph Spectra. - Andries E. Brouwer; Willem H. Haemers (Eur. J. Comb., 1993)

A Design and a Code Invariant under the Simple Group Co3. - Willem H. Haemers; Christopher Parker; Vera Pless; Vladimir D. Tonchev (J. Comb. Theory A, 1993)

Quasi-Symmetric Designs Related to the Triangular Graph. - Matthijs J. Coster; Willem H. Haemers (Des. Codes Cryptogr., 1995)

Spreads in Strongly Regular Graphs. - Willem H. Haemers; Vladimir D. Tonchev (Des. Codes Cryptogr., 1996)

Disconnected Vertex Sets and Equidistant Code Pairs. - Willem H. Haemers (Electron. J. Comb., 1997)

Graphs with constant µ and µ_. - Edwin R. van Dam; Willem H. Haemers (Discret. Math., 1998)

Binary Codes of Strongly Regular Graphs. - Willem H. Haemers; René Peeters; Jeroen M. van Rijckevorsel (Des. Codes Cryptogr., 1999)

Minimum resolvable coverings with small parallel classes. - Willem H. Haemers (Discret. Math., 1999)

The Search for Pseudo Orthogonal Latin Squares of Order Six. - Frans C. Bussemaker; Willem H. Haemers; Edward Spence (Des. Codes Cryptogr., 2000)

The Pseudo-geometric Graphs for Generalized Quadrangles of Order (3, t). - Willem H. Haemers; Edward Spence (Eur. J. Comb., 2001)

Bicliques and Eigenvalues. - Willem H. Haemers (J. Comb. Theory B, 2001)

Johan Jacob Seidel 1919-2001. - Eiichi Bannai; Willem H. Haemers; Patrick Solé (Eur. J. Comb., 2004)

Enumeration of cospectral graphs. - Willem H. Haemers; Edward Spence (Eur. J. Comb., 2004)

Preface. - Aart Blokhuis; Willem H. Haemers (Des. Codes Cryptogr., 2005)

Self-dual, not self-polar. - Andries E. Brouwer; Peter J. Cameron; Willem H. Haemers; Donald A. Preece (Discret. Math., 2006)

5-chromatic strongly regular graphs. - Nick C. Fiala; Willem H. Haemers (Discret. Math., 2006)

Characterizing distance-regularity of graphs by the spectrum. - Edwin R. van Dam; Willem H. Haemers; Jacobus H. Koolen; Edward Spence (J. Comb. Theory A, 2006)

On 3-chromatic distance-regular graphs. - Aart Blokhuis; Andries E. Brouwer; Willem H. Haemers (Des. Codes Cryptogr., 2007)

Geometric and algebraic combinatorics. - Edwin R. van Dam; Willem H. Haemers (Eur. J. Comb., 2007)

Developments on spectral characterizations of graphs. - Edwin R. van Dam; Willem H. Haemers (Discret. Math., 2009)

Matchings in regular graphs from eigenvalues. - Sebastian M. Cioaba; David A. Gregory; Willem H. Haemers (J. Comb. Theory B, 2009)

Strongly regular graphs with parameters (4m4, 2m4+m2, m4+m2, m4+m2) exist for all m>1. - Willem H. Haemers; Qing Xiang (Eur. J. Comb., 2010)

An odd characterization of the generalized odd graphs. - Edwin R. van Dam; Willem H. Haemers (J. Comb. Theory B, 2011)

Divisible design graphs. - Willem H. Haemers; Hadi Kharaghani; Maaike A. Meulenberg (J. Comb. Theory A, 2011)

Matrices for graphs, designs and codes. - Willem H. Haemers (Information Security, Coding Theory and Related Combinatorics, 2011)

Cospectral Graphs and Regular Orthogonal Matrices of Level 2. - Aida Abiad; Willem H. Haemers (Electron. J. Comb., 2012)

The graph with spectrum 141 240 (-4)10 (-6)9. - Aart Blokhuis; Andries E. Brouwer; Willem H. Haemers (Des. Codes Cryptogr., 2012)

Preface: Geometric and algebraic combinatorics. - Edwin R. van Dam; Willem H. Haemers (Des. Codes Cryptogr., 2012)

The maximum order of adjacency matrices of graphs with a given rank. - Willem H. Haemers; M. J. P. Peeters (Des. Codes Cryptogr., 2012)

Spectral characterizations of almost complete graphs. - Marc Cámara; Willem H. Haemers (Discret. Appl. Math., 2014)

Walk-regular divisible design graphs. - Dean Crnkovic; Willem H. Haemers (Des. Codes Cryptogr., 2014)

Regular graphs with maximal energy per vertex. - Edwin R. van Dam; Willem H. Haemers; Jack H. Koolen (J. Comb. Theory B, 2014)

Cospectral regular graphs with and without a perfect matching. - Zoltán Blázsik; Jay Cummings; Willem H. Haemers (Discret. Math., 2015)

Switched symplectic graphs and their 2-ranks. - Aida Abiad; Willem H. Haemers (Des. Codes Cryptogr., 2016)

Preface to the special issue dedicated to Andries E. Brouwer. - Aart Blokhuis; Edwin R. van Dam; Willem H. Haemers; Jack H. Koolen (Des. Codes Cryptogr., 2017)

The graphs with all but two eigenvalues equal to -2 or 0. - Sebastian M. Cioaba; Willem H. Haemers; Jason R. Vermette (Des. Codes Cryptogr., 2017)

On the Spectral Characterization of Mixed Extensions of P3. - Willem H. Haemers; Sezer Sorgun; Hatice Topcu (Electron. J. Comb., 2019)

The graphs cospectral with the pineapple graph. - Hatice Topcu; Sezer Sorgun; Willem H. Haemers (Discret. Appl. Math., 2019)

Graph switching, 2-ranks, and graphical Hadamard matrices. - Aida Abiad; Steve Butler; Willem H. Haemers (Discret. Math., 2019)

Spectral characterization of mixed extensions of small graphs. - Willem H. Haemers (Discret. Math., 2019)

On sign-symmetric signed graphs. - Ebrahim Ghorbani; Willem H. Haemers; Hamid Reza Maimani; Leila Parsaei-Majd (Ars Math. Contemp., 2020)

On NP-hard graph properties characterized by the spectrum. - Omid Etesami; Willem H. Haemers (Discret. Appl. Math., 2020)

Cospectral pairs of regular graphs with different connectivity. - Willem H. Haemers (Discuss. Math. Graph Theory, 2020)

The chromatic index of strongly regular graphs. - Sebastian M. Cioaba; Krystal Guo; Willem H. Haemers (Ars Math. Contemp., 2021)

Spectra of strongly Deza graphs. - Saieed Akbari; Willem H. Haemers; Mohammad Ali Hosseinzadeh; Vladislav V. Kabanov; Elena V. Konstantinova; Leonid Shalaginov (Discret. Math., 2021)

Spectral symmetry in conference matrices. - Willem H. Haemers; Leila Parsaei-Majd (Des. Codes Cryptogr., 2022)

The signed graphs with two eigenvalues unequal to ±1. - Willem H. Haemers; Hatice Topcu (Appl. Math. Comput., 2024)

Divisible design graphs from the symplectic graph. - Bart De Bruyn; Sergey Goryainov; Willem H. Haemers; Leonid Shalaginov (Des. Codes Cryptogr., 2025)