Rayleigh-Schrödinger perturbation theory for electron-phonon interaction in two dimensional quantum dots with asymmetric parabolic potentialY. H. Ren, Q. H. Chen, Y. B. Yu, Z. A. Xu, W. B. Shao and Z. K. JiaoEur. Phys. J. B, 7 4 (1999) 651-656DOI: https://doi.org/10.1007/s100510050658