TY  - RPRT
TI  - The collar button ulcer. A radiologic-pathologic correlation.
AU  - J E Lichtenstein
AU  - J E Madewell
AU  - D S Feigin
PY  - 1979
DO  - 10.1007/bf01887501
UR  - https://pubmed.ncbi.nlm.nih.gov/761749/
ID  - 761749
ER  -