The relationship of Ca-plage areas and other solar Activity indices with ionospheric characteristics In E and F layers. MAUSAM, [S. l.], v. 25, n. 2, p. 305–309, 1974. DOI: 10.54302/mausam.v25i2.5209. Disponível em: https://mausamjournal.imd.gov.in/index.php/MAUSAM/article/view/5209. Acesso em: 29 dec. 2025.