M.Sushanth Babu and  P.Krishna and  U.Venu and  M.Ranjith,  Optimization of Quantization in Higher Order Modulations for LDPC-Coded Systems.   journal   = {International Journal of Electronics and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    January 2012, vol. 61(1). 75 - 81
    [viewed 21 September 2020]. Available from: https://publications.waset.org/pdf/10430.