Karshenboim, Savely G. Laser Spectroscopy, Max Planck Institute of Quantum Optics, Max Planck Society;
Lee, R. N., Milstein, A. I., Terekhov, I. S., & Karshenboim, S. G. (2005). Virtual light-by-light scattering and the g factor of a bound electron. Physical Review A, 71(5): 052501. doi:10.1103/PhysRevA.71.052501.