@article {welch_algorithmic_1982,
	title = {Algorithmic complexity: three NP-hard problems in computational statistics},
	journal = {Journal of Statistical Computation and Simulation},
	volume = {15},
	number = {1},
	year = {1982},
	pages = {17{\textendash}25},
	url = {http://www.tandfonline.com/doi/abs/10.1080/00949658208810560},
	author = {Welch, William J.}
}
