Changes

Cooper-Rand is listed by U.S. Food and Drug Administration (FDA) medical devices catalogue. The registration number of the device is 1525865.<ref>Medical Device Network. Cooper-Rand Electronic Speech Aid. Medical Device Network [online]. Available online at: http://www.medevnet.com/products/index.cfm?fuseaction=products_display_detail&eregnum=1525865&owner_operator_number=1525865&product_code=ESE (Retrieved 16th January, 2017).</ref>

MOFFET, Bethann, PINDZOLA, Rebekah H. [//www.asha.org/uploadedFiles/asha/publications/cicsd/1988AcousticProperties.pdf Acustic Properties of Artifical Larynx Speech]. ASHA [online]. 1988.