Bourne JE, Sauchelli S, Perry R, Page A, Leary S, England C, Cooper AR. Health benefits of electrically-assisted cycling: a systematic review. Int J Behav Nutr Phy. 2018 Nov 21;15(1):116. doi: 10.1186/s12966-018-0751-8
Finkelstein EA, Ruhm C, Kosa KM. Economic causes and consequences of obesity. Annu Rev Public Health. 2005;26:239-57.