Salaffi, Fausto, et al. “Frailty Syndrome in Rheumatoid Arthritis and Symptomatic Osteoarthritis: An Emerging Concept in Rheumatology”. Acta Biomedica Atenei Parmensis, vol. 91, no. 2, May 2020, pp. 274-96, https://doi.org/10.23750/abm.v91i2.9094.