Hammer, P. L., Johnson, E. L., & Korte, B. H. (1979). Discrete optimization: Proceedings of the Advanced Research Institute on Discrete Optimization and Systems Applications of the Systems Science Panel of NATO and of the Discrete Optimization Symposium, co-sponsored by IBM Canada and SIAM, Banff, Alta. and Vancouver, B.C., Canada, August 1977. North-Holland Publishing.

Hammer, P. L., E. L. Johnson, and B. H. Korte. Discrete Optimization: Proceedings of the Advanced Research Institute on Discrete Optimization and Systems Applications of the Systems Science Panel of NATO and of the Discrete Optimization Symposium, Co-sponsored by IBM Canada and SIAM, Banff, Alta. and Vancouver, B.C., Canada, August 1977. Amsterdam: North-Holland Publishing, 1979.

Hammer, P. L., et al. Discrete Optimization: Proceedings of the Advanced Research Institute on Discrete Optimization and Systems Applications of the Systems Science Panel of NATO and of the Discrete Optimization Symposium, Co-sponsored by IBM Canada and SIAM, Banff, Alta. and Vancouver, B.C., Canada, August 1977. North-Holland Publishing, 1979.