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A 1.47-approximation algorithm for a preemptive single-machine scheduling problem
Goemans, Michel X., (2000)
A primal-dual interpretation of two 2-approximation algorithms for the feedback vertex set problem in undirected graphs
Chudak, Fabián A., (1997)
Two-dimensional Gantt charts and a scheduling algorithm of Lawler
GOEMANS, Michel X., (1998)