@article {welch_system_1991, title = {A system for quality improvement via computer experiments}, journal = {Communications in Statistics-Theory and Methods}, volume = {20}, number = {2}, year = {1991}, pages = {477{\textendash}495}, url = {http://www.tandfonline.com/doi/abs/10.1080/03610929108830510}, author = {Welch, William J. and Sacks, Jerome} }