TY  - RPRT
TI  - The evolution of chronic back pain problems: a longitudinal study.
AU  - H C Philips
AU  - L Grant
PY  - 1991
DO  - 10.1016/0005-7967(91)90127-o
UR  - https://pubmed.ncbi.nlm.nih.gov/1835836/
ID  - 1835836
ER  -