8.
Skarżyński H, Lorens A, D’Haese P, Walkowiak A, Piotrowska A, Śliwa L et al. Preservation of residual hearing in children and post-lingually deafened adults after cochlear implantation: an initial study. ORL J Otorhinolaryngol Relat Spec, 2002; 64(4): 247–53.