used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Centre_of_Vision_(IA_centreofvision1910unse_4).pdf...
used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Centre_of_Vision_(IA_centreofvision1910unse).pdf...
used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Centre_of_Vision_(IA_centreofvision1910unse_0).pdf...
used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Centre_of_Vision_(IA_centreofvision1910unse_3).pdf...