1. The Deaf Schoolchild: Language and Cognitive Function;Conrad,1979
2. Prevention of Blindness and Deafness, World Health Organization (Geneva) Global estimates for hearing impairment, 2001 http://www.who.org/pbp/deafness.
3. World Health Organization, Leading causes of YLD in Oman for 2000 (November) 2002 (EBD/GPE/EIP) http://www.who.int/evidence/bod.
4. NIH recommends universal screening of infants for hearing impairment;Am. Fam. Physician,1993
5. The efficacy of early identification and intervention for children with hearing impairment;Downs;Pediatr. Clin. N. Am.,1999