1. Gyton, A.C., Hall, J.E.: Textbook of Medical Physiology, 11th edn. Elsevier Saunders, Philadelphia, Pennsylvania (2006)
2. Clark C., Clark M.: Health Revolution for Men: Kick-start Your Weight Loss and Reduce Your Risk of Serious Disease. Hachette Digital, London (2012)
3. Wiker, S.F., Chaffin, D.B., Langolf, G.D.: Shoulder posture and localized muscle fatigue and discomfort. Ergonomics 32(2), 211–237 (1989)
4. Middlesworth M.: http://ergo-plus.com/fundamental-ergonomic-principles/
5. Reese, C.D.: Occupational Health and Safety Management: A Practical Approach. Lewis Publishers, Washington, D.C. (2003)