1. Spontaneous osteonecrosis of the knee;Ahlback;Arthritis Rheum,1968
2. Painful knees in older patients;Lotke,1977
3. Osteonecrosis of the knee;Bauer;Clin Orthop,1978
4. Current concepts review;Lotke,1988
5. Osteonecrosis of the knee;Lotke;Orthop Clin North Am,1985