TY  - RPRT
TI  - Observer dependence in quantum cosmology.
AU  - E Calzetta
AU  - A Kandus
PY  - 1993
DO  - 10.1103/physrevd.48.3906
UR  - https://pubmed.ncbi.nlm.nih.gov/10016666/
ID  - 10016666
ER  -