[1]
C. H. Mandrini, L. van Driel-Gresztelyi, B. Thompson, S. Punkett, P. Démoulin, and G. Aulanier, “Evolution and decay of an active region: Magnetic shear, flare and CME activity”, Geofis Int, vol. 39, no. 1, pp. 73–80, Jan. 2000.