1. Red Book;CCITT Recommendation G.162,1985
2. Transmission Systems for Communications, Bell Telephone Laboratories Inc., Chaps. 9, 28.
3. INTELSAT Document BG/T-31–37E, Report on Companded FDM/FM, Jan. 1980.
4. Proc. IRE;EM Rizzoni,1960
5. Proc. IRE;RG Medhurst,1956