Differences in physical health across populations and their implications for the old-age dependency ratio in high-, middle- and low-income countries. SSM - Population Health. 2020;11. doi:10.1016/j.ssmph.2020.100579..
Time to Burn (Calories)? The Impact of Retirement on Physical Activity among Mature Americans. Journal of Health Economics. 2016;45:91-102. doi:http://dx.doi.org/10.1016/j.jhealeco.2015.12.001..