Published online by Cambridge University Press: 14 August 2015
Since Gershberg's (1970a) very thorough review of the subject, numerous papers dealing with the collective properties of flare stars have appeared (Petit, 1970; Kunkel, 1970d, 1973; Ambartsumian and Mirzoyan, 1971; Gurzadyan, 1971; Oskanian and Terebizh, 1971a, b; Gershberg, 1972; Veeder, 1973). The basic features of flare activity can be taken as known, then.