TY  - RPRT
TI  - Posttraumatic headache: determining chronicity.
AU  - R C Packard
AU  - L P Ham
PY  - 1993
DO  - 10.1111/j.1526-4610.1993.hed3303133.x
UR  - https://pubmed.ncbi.nlm.nih.gov/8486509/
ID  - 8486509
ER  -