Engebretson, T., Clark, M., Niaura, R., Phillips, T., Albrecht, A., & Tilkemeier, P. (1999). Quality of life and anxiety in a phase II cardiac rehabilitation program. Medicine and science in sports and exercise, 31(2), S. 216-223.

Engebretson, T.O., M.M Clark, R.S Niaura, T. Phillips, A. Albrecht, and P. Tilkemeier. "Quality of Life and Anxiety in a Phase II Cardiac Rehabilitation Program." Medicine and Science in Sports and Exercise 31, no. 2 (1999): S. 216-223.

Engebretson, T.O., et al. "Quality of Life and Anxiety in a Phase II Cardiac Rehabilitation Program." Medicine and Science in Sports and Exercise 31.2 (1999): S. 216-223.