@article{Afshani.Hatami.IPL08,
	title = {Approximation and inapproximability results for maximum clique of disc graphs in high dimensions},
	author = {Peyman Afshani and Hamed Hatami},
	journal = {Information Processing Letters},
	volume = {105},
	issue = {3},
	month = {January},
	year = {2008},
	pages = {83--87}
}