Characteristics of tracheostomy phonation valves
H. Prigent, D. Orlikowski, M. B. Blumen, K. Leroux, L. Legrand, M. Lejaille, L. Falaize, M. Ruquet, J-C. Raphael, F. Lofaso
European Respiratory Journal May 2006, 27 (5) 992-996; DOI: 10.1183/09031936.06.00009405