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
Garcia-Albeniz X, Chan AT. Aspirin for the prevention of colorectal cancer. Best Pract Res Clin Gastroenterol. 2011 Aug;25(0):461-72. doi: 10.1016/j.bpg.2011.10.015
Cohen LM, Britt DM, Collins FL, Stott HD, Carter LC. Chewing gum affects smoking topography. Exp Clin Psychopharmacol. 1999 Nov 1;7(4):444-7.