Syarifah; Desinora Natalia Hutauruk; Diancrisy Situmeang; Maria Innest; Siti Nurhidayah Al-Anshari. Biography of Willem Iskandar and His Role in Education In North Sumatra: Biografi Willem Iskandar Dan Perannya Dalam Pendidikan Di Sumatera Utara. JS 2024, 8, 402-407.