Voloshin, M.(1997). Large O(mc−2) nonperturbative corrections to the inclusive rate of the decay B → Xsγ. Physics Letters B, 397(3-4), 275-278. doi:10.1016/s0370-2693(97)00173-1

Voloshin, M.B. "Large O(mc−2) Nonperturbative Corrections to the Inclusive Rate of the Decay B → Xsγ". Physics Letters B, 397.3-4 ( 1997 ): 275-278.