Hayes AF, Montoya AK, Rockwood NJ. The analysis of mechanisms and their contingencies: PROCESS versus structural equation modeling. AMJ. 2017 Feb;25(1):76-81. doi: 10.1016/j.ausmj.2017.02.001
Norton EC, Zarkin GA, Calingaert B, Bradley CJ. The effect of maternal substance abuse on the cost of neonatal care. Inquiry. 1996;33(3):247-57.