KEBERAGAMAN SISTEM KALENDER UMAT ISLAM PERSPEKTIF TEORI DIFERENSIASI SOSIAL HERBERT SPENCER. ahkam [Internet]. 2014 Jul. 1 [cited 2026 Jan. 24];2(1):4-19. Available from: https://ejournal.uinsatu.ac.id/index.php/ahkam/article/view/678