Natascya Putri Siburian, Rudyn Reymond Panjaitan, and Joseph Partogi Sibarani, “Profile of Serum Folate Levels in Various Severity Degrees of Psoriasis Vulgaris Patients at Murni Teguh Memorial Hospital Medan”, JUK-Medifa, vol. 4, no. 02, pp. 102–107, Jul. 2026.