Zorkany, B. E., A. Mokbel, S. M. Gamal, I. Hmamouchi, and M. Dougados,  "Does smoking afect level of seropositivity in RA? A post?HOC global  and inter?country analysis of COMORA cohort",  Rheumatology International, vol. 41, issue 4, pp. 699 - 705, 2021.