論文（英文）
Efficiency of ultrasensitive prostate-specific antigen assay in diagnosing biochemical failure after radical prostatectomy.
Shimizu F, Tanaka S, Matsuyama Y, Tominaga T, Ohashi Y, and Fujime M. Efficiency of ultrasensitive prostate-specific antigen assay in diagnosing biochemical failure after radical prostatectomy. Japanese Journal of Clinical Oncology 2007; 37: 446-451.