(1)
shojai, M.; Kazemnejad, A.; Zayeri, F.; Vahedi, M. Application of Semi-Parametric Single-Index Two-Part Regression and Parametric Two-Part Regression in Estimation of the Cost of Functional Gastrointestinal Disorders. Gastroenterol Hepatol Bed Bench 2013, 6, Gastroenterol Hepatol Bed Bench 2013;6(4):202-209.