Observing Variable Stars (Patrick Moore's Practical Astronomy Series) (2003. VIII, 274 p. w. 55 figs. 23,5 cm)

Observing variable stars is one of the major contributions amateur astronomers make to science. There are 36,000 variable stars listed in the General Catalogue of Variable Stars, so it is clearly impossible for the limited number of professional observatories to target even the majority of them.