Siregar, Chandra A, Affandi Affandi, Ahmad Marabdi Siregar, and M D Nasution. “Pemetaan Potensi Radiasi Matahari Di Sumatera Utara Berdasarkan Perhitungan Matematika”. Seminar Nasional Teknologi Edukasi Sosial dan Humaniora 1, no. 1 (August 25, 2021): 72–77. Accessed October 22, 2025. https://jurnal.ceredindonesia.or.id/index.php/sintesa/article/view/207.