TY  - RPRT
TI  - Wigner distribution function and phase-space formulation of quantum cosmology.
AU  - E Calzetta
AU  - BL Hu
PY  - 1989
DO  - 10.1103/physrevd.40.380
UR  - https://pubmed.ncbi.nlm.nih.gov/10011826/
ID  - 10011826
ER  -