H. L. Bodlaender, T. Kloks, R. B. Tan, and J. Van-leeuwen, Approximations for ??-Colorings of Graphs, The Computer Journal, vol.47, issue.2, pp.193-204, 2004.
DOI : 10.1093/comjnl/47.2.193

G. J. Chang and D. Kuo, The $L(2,1)$-Labeling Problem on Graphs, SIAM Journal on Discrete Mathematics, vol.9, issue.2, pp.309-316, 1996.
DOI : 10.1137/S0895480193245339

J. Fiala, P. Golovach, and J. Kratochvíl, Distance Constrained Labelings of Graphs of Bounded Treewidth, Proceedings of ICALP 2005, pp.360-372, 2005.
DOI : 10.1007/11523468_30

J. Fiala, T. Kloks, and J. Kratochvíl, Fixed-parameter complexity of ??-labelings, Discrete Applied Mathematics, vol.113, issue.1, pp.59-72, 2001.
DOI : 10.1016/S0166-218X(00)00387-5

J. Fiala and J. Kratochvíl, Complexity of Partial Covers of Graphs, Proceedings of ISAAC 2001, pp.537-549, 2001.
DOI : 10.1002/(SICI)1097-0118(199812)29:4<263::AID-JGT5>3.0.CO;2-V

J. Fiala and J. Kratochvíl, Partial covers of graphs, Discussiones Mathematicae Graph Theory, vol.22, issue.1, pp.89-99, 2002.
DOI : 10.7151/dmgt.1159

J. Fiala, J. Kratochvíl, and A. Pór, On the computational complexity of partial covers of Theta graphs, Electronic Notes in Discrete Mathematics, vol.19, pp.79-85, 2005.
DOI : 10.1016/j.endm.2005.05.012

F. Fomin, F. Grandoni, and D. Kratsch, Measure and Conquer: Domination ??? A Case Study, Proceedings of ICALP 2005, pp.192-203, 2005.
DOI : 10.1007/11523468_16
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.77.1085

F. Fomin, P. Heggernes, and D. Kratsch, Exact Algorithms for Graph Homomorphisms, Theory of Computing Systems, vol.41, issue.2, pp.381-393, 2007.
DOI : 10.1007/s00224-007-2007-x
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.109.7780

D. Gonçalves, On the L(p, 1)-labelling of graphs, DMTCS Proceedings Volume AE, pp.81-86

J. R. Griggs and R. K. Yeh, Labelling Graphs with a Condition at Distance 2, SIAM Journal on Discrete Mathematics, vol.5, issue.4, pp.586-595, 1992.
DOI : 10.1137/0405048

F. Havet, B. Reed, and J. Sereni, 1)-labellings of graphs, Proceedings of SODA 2008, pp.621-630, 2008.

P. Hell and J. Ne?et?il, On the complexity of H-coloring, Journal of Combinatorial Theory, Series B, vol.48, issue.1, pp.92-110, 1990.
DOI : 10.1016/0095-8956(90)90132-J

J. Kratochvíl, D. Kratsch, and M. Liedloff, Exact Algorithms for L(2,1)-Labeling of Graphs, Proceedings of MFCS 2007, pp.513-524, 2007.
DOI : 10.1007/978-3-540-74456-6_46

R. A. Leese, N. , and S. D. , Cyclic labellings with constraints at two distances, Electronic Journal of Combinatorics, vol.11, 2004.

D. Liu and X. Zhu, Multilevel Distance Labelings for Paths and Cycles, SIAM Journal on Discrete Mathematics, vol.19, issue.3, pp.610-621, 2005.
DOI : 10.1137/S0895480102417768
URL : http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.95.3352

D. Liu and X. Zhu, Circular Distance Two Labelings and Circular Chromatic Numbers, Ars Combinatoria, vol.69, pp.177-183, 2003.