Peremennye Zvezdy

collections of articles published by the Astronomical Council of the Academy of Sciences of the USSR. Begun in 1928 by a group of amateur astronomers and physicists in Nizhny Novgorod, the collections have been published since 1946 in Moscow (until 1971 as a bulletin). They include results of studies of variable stars, quasars, X-ray sources, and other cosmic objects exhibiting unstable behavior, as well as methodological and theoretical work connected with these objects. By the beginning of 1975, a total of 141 issues and six supplements had appeared.