1 "Fișier:Acoustics_of_auditoriums_(IA_acousticsofaudit00watsrich).pdf".

Fișier:Acoustics of auditoriums (IA acousticsofaudit00watsrich).pdf

sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Acoustics_of_auditoriums_(IA_acousticsofaudit00watsrich).pdf...