1. Un seguno poco note e sua importanza per la diagnosi precoce di prelussazione congenita dell'anca.;Ortolani;Pediatria,1937
2. Congenital hip dysplasia in the light of early and very early diagnosis.;Ortolani;Clin Orthop Relat Res,1976
3. Instability of the hip in the newborn. Classification for selective treatment; pathogenesis of the dislocation and complications.;Fellander;Acta Orthop Scand Suppl,1970
4. Neonatal screening for congenital dislocation of the hip. A prospective 21-year survey.;Hadlow;J Bone Joint Surg Br,1988
5. Problems encountered in the early diagnosis and management of congenital dislocation of the hip.;Mackenzie;J Bone Joint Surg Br,1981