Villarroel, B., Soodla, J., Comerón, S., Mattsson, L., Pelckmans, K., López-Corredoira, M., Krisciunas, K., Guerras, E., Kochukhov, O., Bergstedt, J., Buelens, B., Bär, R. E., Cubo, R., Enriquez, J. E., Gupta, A. C., Imaz, I., Karlsson, T., Prieto, M. A., Shlyapnikov, A. A., de Souza, R. S., …Ward, M. J. (2020). The Vanishing and Appearing Sources during a Century of Observations Project. I. USNO Objects Missing in Modern Sky Surveys and Follow-up Observations of a “Missing Star”. Astronomical Journal, 159(1), Article 8. https://doi.org/10.3847/1538-3881/ab570f