The magnesium paradigm in IRC +10216: Discovery of MgC4H+, MgC3N+, MgC6H+, and MgC5N+ J. Cernicharo, C. Cabezas, J. R. Pardo, M. Agúndez, O. Roncero, B. Tercero, N. Marcelino, M. Guélin, Y. Endo and P. de Vicente A&A, 672 (2023) L13 Published online: 21 April 2023 DOI: 10.1051/0004-6361/202346467