Oschman, Z, et al. “Ultrasound Study of the Asymptomatic Shoulder in Patients With a Confirmed Rotator Cuff Tear in the Opposite Shoulder”. South African Journal of Sports Medicine, vol. 19, no. 1, Mar. 2007, pp. 23-28, doi:10.17159/2078-516X/2007/v19i1a272.