The extracellular remodeling of free-soft-tissue autografts and allografts for reconstruction of the anterior cruciate ligament: a comparison study in a sheep model. - Dustmann, M.; Schmidt, T.; Gangey, I.; Unterhauser, F. N.; Weiler, A.; Scheffler, S. U. (Knee Surgery, Sports Traumatology, Arthroscopy, 2008)