TY  - RPRT
TI  - Spurious singularities in the Schwinger variational method.
AU  - C Winstead
AU  - V McKoy
PY  - 1990
DO  - 10.1103/physreva.41.49
UR  - https://pubmed.ncbi.nlm.nih.gov/9902839/
ID  - 9902839
ER  -