TY  - RPRT
TI  - Finite-basis-set variational solution of the Dirac equation.
AU  - AB Volkov
PY  - 1989
DO  - 10.1103/physreva.39.4406
UR  - https://pubmed.ncbi.nlm.nih.gov/9901788/
ID  - 9901788
ER  -