1. 1. S. Kirkpatrick; C. D. Gelatt; M. P. Vecchi, “Optimization by Simulated Annealing,” ScienceNew Series, Vol. 220, pp. 671-680, 1983.
   2. E. H. L.Aarts and J. K. Lenstra, “Local Search in Combinatorial optimization,” John Wiley & Sons, Chichester, 1997.
   3. D. E. Goldberg, “Genetic Algorithms in Search, Optimization and Machine Learning,” Addison – Wesley, 1989.
   4. S. Voss, S. Martello and I.H. Osman, “MetaHeuristics: Advances and trends in Local Search Paradigms for Optimization,” Kluwer Academic Publishers, Boston, MA, 1999.
   5. F. Glover and M. Laguna,,“Tabu Search,” Kluwer Academic Publishers, Boston, MA, 1997.
   6. M. Dorigo, V. Maniezzo, and A. Colorni, “The Ant System: Optimization by a colony of cooperating agents,” IEEE transcations on Systems, Man, and Cybernetics, vol. 26, pp. 29-41, 1996.
   7. M.Dorigo and T. Stutzle, “Ant Colony Optimization,” MIT Press, Cambridge, MA, 2004.
   8.  E. Bonabeau, M. Dorigo, and G. Theraulaz, “Swarm Intelligence: From Natural to Artificial Systems,” Oxford University