See page 154.
Manipulating The Ether: The Power Of Broadcast Radio In Thirties America By Robert J. Brown
http://books.google.com/books?id=12dk9bizqIAC&printsec=frontcover&dq=manipulating+the+ether+robert+brown&source=bl&ots=KG5pAfVEug&sig=3m7HD9v63o4fA1t7GqzQaE0wOF4&hl=en&ei=vb0ETfiEOMGblgec4MTYCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBcQ6AEwAA#v=onepage&q&f=false
Thank you