1. Congenital dysplasia and dislocation of the hip in children and adults;Tonnis,1987
2. Contribution to the knowledge of congenital dislocation of the hip; late results of closed reduction and arthrographic studies of recent cases;Severin;Acta Chir Scand,1941
3. Studies on dysplastic acetabula and congenital subluxation of the hip joint; with special reference to the complication of osteoarthritis;Wiberg;Acta Chir Scand,1939
4. Reliability of the Severin classification in the assessment of developmental dysplasia of the hip;Ali;J Pediatr Orthop B,2001
5. Severin classification system for evaluation of the results of operative treatment of congenital dislocation of the hip; A study of intraobserver and interobserver reliability;Ward;J Bone Joint Surg Am,1997