TY  - RPRT
TI  - Spin networks and quantum gravity.
AU  - C Rovelli
AU  - L Smolin
PY  - 1995
DO  - 10.1103/physrevd.52.5743
UR  - https://pubmed.ncbi.nlm.nih.gov/10019107/
ID  - 10019107
ER  -