Bergemann, M. Stellar Astrophysics, MPI for Astrophysics, Max Planck Society;
Jofré, P., Heiter, U., Soubiran, C., Blanco-Cuaresma, S., Worley, C. C., Pancino, E., et al. (2014). Gaia FGK benchmark stars: metallicity. Astronomy & Astrophysics, 564: A133, pp. 1-27. doi:10.1051/0004-6361/201322440.