Karshenboim, Savely G. Laser Spectroscopy, Max Planck Institute of Quantum Optics, Max Planck Society;
Karshenboim, S. G., Korzinin, E. Y., & Ivanov, V. G. (2014). Relativistic recoil effects on energy levels in a muonic atom: A Grotch-type calculation of the second-order vacuum-polarization contributions. Physical Review A, 89(3): 032129. doi:10.1103/PhysRevA.89.032129.