United States. Federal Communications Commission. FCC Record, Volume 2, No. 13, Pages 3683 to 4000, June 22 - July 2, 1987, book, July 1987; (https://digital.library.unt.edu/ark:/67531/metadc1598/m1/1/: accessed November 13, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .