M. John and A. Karrenbauer, A Novel SDP Relaxation for the Quadratic Assignment Problem Using Cut Pseudo Bases, Lecture Notes in Computer Science, pp.414-425, 2016.
DOI : 10.1007/s10107-008-0235-8

A. Karrenbauer and A. Oulasvirta, Improvements to keyboard optimization with integer programming, Proceedings of the 27th annual ACM symposium on User interface software and technology, UIST '14, 2014.
DOI : 10.1145/2642918.2647382

L. Kaufman and F. Broeckx, An algorithm for the quadratic assignment problem using Bender's decomposition, European Journal of Operational Research, vol.2, issue.3, pp.207-211, 1978.
DOI : 10.1016/0377-2217(78)90095-4

M. Feit, D. Weir, and A. Oulasvirta, How We Type, Proceedings of the 2016 CHI Conference on Human Factors in Computing Systems, CHI '16, 2016.
DOI : 10.1145/2470654.2481384