1. Allen, M. G., Dowler, P., Evans, J. D., Cui, C., Jenness, T., Merin, B., Berriman, G. B., & Kavelaars, J. J. (for the IVOA Executive Committee and Technical Coordination Group), The International Virtual Observatory Alliance in 2019, arXiv:1912.0148IvI [astro-ph.IM], 3 Dec 2019.
2. About the four million star catalog. Collection of scientific papers edited by Gulyaev A. and Nesterov V., Publishing house of Moscow State University, 1992
3. Berger, J., Cordoni, J. P., Fringant, A. M., Guibert, J., Moreau, O., Reboul, H., & Vanderriest, C. (1991). Astrometric study of 1221 UV-excess objects at the North Galactic Pole. Astronomy & Astrophysics Supplements, 87, 389.
4. Berriman, B., Kirkpatrick, D., Hanisch, R., Szalay, A., & Williams, R. (2003). Discover of Brown Dwarfs with Virtua Observatories. IAU Joint Discussion, 25, 60.
5. Caballero, J., & Dinis, L. (2008). A revisit to agglomerates of early-type Hipparcos stars. AN, 329, 801.