Engelhart L, Nelson L, Lewis S, Mordin M, Demuro-Mercon C, Uddin S, McLeod L, Cole B, Farr J. Knee injury and osteoarthritis outcome score subscales for patients with articular cartilage lesions of the knee. Am J Sports Med. 2012 Oct 1;40(10):2264-72.
Britt DM, Cohen LM, Collins FL, Cohen ML. Cigarette smoking and chewing gum: response to a laboratory-induced stressor. Health Psychol. 2001 Sep 1;20(5):361-8.