Syarif , Muh Rasywan, and Naif. 2017. “Konsolidasi Metodologis Kalender Islam Internasional: Meneladani Intelektual Umar Bin Khattab Dan Julius Caesar”. Jurnal Bimas Islam 10 (3):517-38. https://doi.org/10.37302/jbi.v10i3.33.