Mass spectra of hidden heavy-flavor tetraquarks with two and four heavy quarks Ting-Qi Yan, Wen-Xuan Zhang and Duojie Jia Eur. Phys. J. C, 83 9 (2023) 810 Published online: 11 September 2023 DOI: 10.1140/epjc/s10052-023-11956-3