Physics of the sapphire whispering-gallery-mode solid-state MASER oscillatorMohamad Mrad, Ahmad Tarhini, Pierre-Yves Bourgeois and Vincent GiordanoEur. Phys. J. Appl. Phys., 91 3 (2020) 31001DOI: https://doi.org/10.1051/epjap/2020200107
