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Lemaréchal, Claude (2001). “Lagrangian relaxation”. Trong Michael Jünger and Denis Naddef (biên tập). Computational combinatorial optimization: Papers from the Spring School held in Schloß Dagstuhl, May 15–19, 2000. Lecture Notes in Computer Science. 2241. Berlin: Springer-Verlag. tr. 112–156. doi:10.1007/3-540-45586-8_4. ISBN3-540-42877-1. MR1900016.