Half-integral linear programming relaxation for scheduling precedence-constrained jobs on a single machineFabián A. ChudakDorit S. Hochbaum1999Operations Research Letters
A primal-dual interpretation of two 2-approximation algorithms for the feedback vertex set problem in undirected graphsFabián A. ChudakMichel X. Goemanset al.1998Operations Research Letters
Tight bounds and 2-approximation algorithms for integer programs with two variables per inequalityDorit S. HochbaumNimrod Megiddoet al.1993Mathematical Programming