Tribolet de Abreu, Tiago, António Panarra, Ana Ferreira, Francisco Soromenho, and Manuel Vaz Riscado. 2000. “Rheumatoid Arthritis: Extra-Articular Manifestations, Immunology and the Role of Methotrexate”. Internal Medicine 7 (3). Lisboa, Portugal:150-55. https://revista.spmi.pt/index.php/rpmi/article/view/1995.