@article {gugr2009statsci,
	title = {Interval estimation for messy observational data},
	journal = {Statistical Science},
	volume = {24},
	year = {2009},
	pages = {328-342},
	doi = {10.1214/09-sts305},
	url = {http://projecteuclid.org/euclid.ss/1270041259},
	author = {Gustafson, P. and Greenland, S.}
}
