GCVS Abbrev. for General Catalog of Variable Stars , a publication providing a comprehensive list of variable objects compiled under the direction of the Russian astronomer P.N. Kholopov. The fourth edition in its printed form (1985–90) listed 28 484 stars that had been confirmed as variables by 1982, giving their positions for the epoch 1950.0. The most salient sections of its five volumes are available in computerized form from the Sternberg Institute, Moscow. The first four volumes deal with variable stars within the Milky Way system, the fifth catalogs 10 979 variables in 35 extragalactic star systems, including the Magellanic Clouds and the Andromeda and Triangulum galaxies. There is also a catalog of 984 confirmed and suspected extragalactic supernovae. The New Catalog of Suspected Variable Stars (compiled by B.V. Kukarkin et al and published in its latest revision in 1982) gives the positions, magnitudes, variability types and alternative identifications of 14 811 stars whose variability was still not confirmed before 1980; a supplement to this publication lists 11 206 stars that were still unconfirmed as variables by 1997.