AKANIRU, A.; ONUCHUKWU, C. Statistical Analysis Of Sunspot Number And Area. COOU Journal of Multidisciplinary Studies, [S. l.], v. 1, n. 1, p. 107–121, 2017. Disponível em: https://cjoms.coou.edu.ng/index.php/journal/article/view/9. Acesso em: 18 may. 2024.