@article {14548,
	title = {Approximation Algorithms for Non-Uniform Buy-at-Bulk Network Design},
	journal = {SIAM Journal on Computing},
	volume = {39},
	year = {2010},
	month = {2010///},
	pages = {1772 - 1798},
	author = {Chekuri,C. and Hajiaghayi, Mohammad T. and Kortsarz,G. and Salavatipour,M. R}
}
