The Equivalence of Variational and Perturbation Calculations of Small Disturbances

A Dalgarno¹ and J T Lewis¹

Published under licence by IOP Publishing Ltd
Proceedings of the Physical Society. Section A, Volume 69, Number 8 Citation A Dalgarno and J T Lewis 1956 Proc. Phys. Soc. A 69 628 DOI 10.1088/0370-1298/69/8/408