Off diagonal charged scalar couplings with the Z boson: Zee-type models as an example Ricardo R. Florentino, Jorge C. Romão and João P. Silva Eur. Phys. J. C, 81 12 (2021) 1148 Published online: 31 December 2021 DOI: 10.1140/epjc/s10052-021-09956-2