1.
Turovsky A. Expansion of the Two-particle Dirac Equation in Powers of 1/c to Higher Orders. Ukr. J. Phys. [Internet]. 2022 Feb. 17 [cited 2024 Jul. 27];56(1):5. Available from: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2022149