Vetrano DL, Foebel AD, Marengoni A, Brandi V, Collamati A, Heckman GA, Hirdes J, Bernabei R, Onder G.  2016.  Chronic diseases and geriatric syndromes: The different weight of comorbidity. European Journal of Internal Medicine. 27:62-7.

Egbujie BA, Turcotte LA, Heckman GA, Morris JN, Hirdes JP.  2024.  Functional Decline in Long-Term Care Homes in the First Wave of the COVID-19 Pandemic: A Population-based Longitudinal Study in Five Canadian Provinces. Journal of the American Medical Directors Association. 25(2):282-289.