Wardman M, Chintakayala PK, de Jong G. Values of travel time in Europe: review and meta-analysis. Transp Res Part A Policy Pract. 2016 Dec;94:93-111. doi: 10.1016/j.tra.2016.08.019
Lang K, Meyers JL, Korn JR, Lee S, Sikirica M, Crivera C, Dirani R, Menzin J. Medication adherence and hospitalization among patients with schizophrenia treated with antipsychotics. Psychiatr Serv. 2010 Dec 1;61(12):1239-47.
Britt (DiBenedetti) DM, Collins FL, Cohen LM. Cigarette smoking and chewing gum use among college students. J Appl Biobehav Res. 2007 Jun 4;4(2):85-90. doi: 10.1111/j.1751-9861.1999.tb00057.x