TY - JOUR T1 - Abdominal crunches as an unusual cause of empyema JF - Canadian Medical Association Journal JO - CMAJ SP - 1577 LP - 1578 DO - 10.1503/cmaj.061118 VL - 176 IS - 11 AU - Omar Abouzzeddine AU - Navdeep Tangri Y1 - 2007/05/22 UR - http://www.cmaj.ca/content/176/11/1577.abstract ER -