Echer, E., N. J. Schuch, K. Makita, y S. Okano. 2004. «Observations of Broadband Solar UV-A Irradiance at Santa Maria, Brazil (29°S, 53° W)2004-01-01». Geofísica Internacional 43 (1):53-59. https://doi.org/10.22201/igeof.00167169p.2004.43.1.214.