Abdul Razak, A. H. ., A. H. . Zulkifly, R. Musa, M. S. . Awang, and K. L. Goh. “The Levels of Depression, Anxiety and Stress on Pre and Post Knee Arthroplasty Patients”. IIUM Medical Journal Malaysia, vol. 16, no. 1, June 2017, doi:10.31436/imjm.v16i1.1185.