7Felus J,Kowalczyk B.Clinically silent developmental hip dysplasia significance of the hip ultrasonographic examination.Chir Narzadow Ruchu Ortop Pol, 2005,70( 6 ) : 397-400.
8Bialik V, Bialik GM, Blazer S, et al.Developmental dysplasia of the hip : a new approach to incidence.Pediatrics, 1999, 103 ( 1 ) : 93-99.
9Smergel E, Losik SB, Rosenberg HK,Sonography of hip dysplasia. Uhrasound Q, 2004,20(4 ): 201-216.
10Simon EA, Saur F, Buerge M, et al. Inter-observer agreement of ultrasonographic measurement of alpha and beta angles and thefinal type classification based on the Graf method. Swiss Med Wkly, 2004, 134( 45-46 ) : 671-677.