Radial excitations of heavy-light mesons from QCD sum rulesP. Gelhausen, A. Khodjamirian, A. A. Pivovarov and D. RosenthalEur. Phys. J. C, 74 8 (2014) 2979DOI: https://doi.org/10.1140/epjc/s10052-014-2979-z