[1]ErdÖs P, Gallai T, Tuza Z. Covering the cliques of a graph with vertices[J]. Discrete Math, 1992, 108(1/2/3): 279-289.
[2]Bafna V, Berman P, Fujito T. A 2-approximation algorithm for the undirected feedback vertex set problem[J]. SIAM J Discrete Math, 1999, 12(3): 289-297.
[3]Chudak F A, Goemans M X, Hochbaum D S, et al. A primal-dual interpretation of two 2-approximation algorithms for the feedback vertex set problem in undirected graphs[J]. Operations Research Letters, 1998, 22(4/5): 111-118.
[4]Balachandran V, Nagavamsi P, Rangan C P. Clique transversal and clique independence on comparability graphs[J]. Information Processing Letters, 1996, 58(4): 181-184.
[5]Brešar B, Kardoš F, Katrenič J, et al. Minimum k-path vertex cover[J]. Discrete Applied Mathematics, 2011, 159(12): 1189-1195.