@article {gao_predicting_1996, title = {Predicting urban ozone levels and trends with semiparametric modeling}, journal = {Journal of Agricultural, Biological, and Environmental Statistics}, year = {1996}, pages = {404{\textendash}425}, url = {http://www.jstor.org/stable/1400436}, author = {Gao, Feng and Sacks, Jerome and Welch, William J.} }