W. W. Hager, J. T. Hungerford, and I. Safro, A Multilevel Bilinear Programming Algorithm for the Vertex Separator Problem, Computational Optimization and Applications, Vol. 69 (2018), pp. 189-223. DOI 10.1007/s10589-017-9945-2
W. W. Hager and J. T. Hungerford, Continuous Quadratic Programming Formulations of Optimization Problems on Graphs, European Journal of Operational Research, Vol. 240 (2015), pp. 328-337.
W. W. Hager and J. T. Hungerford, Optimality conditions for maximizing a function over a polyhedron, Mathematical Programming, 145 (2014), pp. 179-198. doi: 10.1007/s10107-013-0644-1
W. W. Hager, D. Phan, and H. Zhang, An exact algorithm for graph partitioning, Mathematical Programming, 137 (2013), pp. 531-556 (DOI 10.1007/s10107-011-0503-x).
W. W. Hager and Y. Krylyuk, Multiset graph partitioning, Mathematical Methods of Operations Research, 55 (2002), 1-10.
W. W. Hager, S. C. Park, and T. A. Davis, Block exchange in graph partitioning (in Approximation and Complexity in Numerical Optimization: Continuous and Discrete Problems, P. M. Pardalos, ed., Kluwer, 2000, pp. 299-307)
W. W. Hager and Y. Krylyuk, Graph partitioning and continuous quadratic programming (SIAM Journal on Discrete Mathematics, 12 (1999), pp. 500-523).
W. W. Hager, Minimizing the profile of a matrix, SIAM Journal on Scientific Computing, 28 (2002), pp. 1799-1816.