Towards a heavy diquark effective theory for weak decays of doubly heavy baryonsYu-Ji Shi, Wei Wang, Zhen-Xing Zhao and Ulf-G. MeißnerEur. Phys. J. C, 80 5 (2020) 398DOI: https://doi.org/10.1140/epjc/s10052-020-7949-z