@article{Schmidt_1989, title={Partitions in the Perturbation-Theory of N-Electron Systems .3. The 3rd-Order Energy}, volume={22}, ISSN={0305-4470}, archiveLocation={Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο}, url={https://hdl.handle.net/10442/6563}, DOI={10.1088/0305-4470/22/11/020 }, number={11}, journal={Journal of Physics A-Mathematical and General}, publisher={Institute of Physics Publishing}, author={Schmidt, H. M.}, year={1989}, pages={1799–1806} }