Persson, Per-Erik, Olle S Nilsson, and Ann-Marie Berggren. 2005. “Do Non-Steroidal Anti-Inflammatory Drugs Cause Endoprosthetic Loosening? A 10-Year Follow-up of a Randomized Trial on Ibuprofen for Prevention of Heterotopic Ossification After Hip Arthroplasty”. Acta Orthopaedica 76 (6):735-40. https://doi.org/10.1080/17453670510045309.