P. Shahbazian, “Decreased Serum Levels of Interleukin-4 and Interleukin-21 in New Pemphigus Vulgaris Patients, but Not Chronic Patients With Inactive Disease Compared to Healthy Controls”, Dermatol Pract Concept, vol. 11, no. 2, p. e2021035, Apr. 2021, doi: 10.5826/dpc.1102a35.