Extended main sequence turnoffs in open clusters as seen by Gaia - II. The enigma of NGC 2509DOI: info:10.1093/mnras/stz3128v. 4912129–2136
de Juan Ovelar, M., Gossage, Seth, Kamann, S., Bastian, N., Usher, C., Cabrera-Ziri, Ivan, Dotter, Aaron, Conroy, Charlie, and Lardo, C. 2020. "Extended main sequence turnoffs in open clusters as seen by Gaia - II. The enigma of NGC 2509." Monthly Notices of the Royal Astronomical Society, 491 2129–2136. https://doi.org/10.1093/mnras/stz3128.