1. Oral Gpps Jr, Western J. Agriculture, Economics, 50–63(1983).
2. Raja Manish, Prude Uni., West Lafayeffe, USA. (2014).
3. S. Neal, IEE digital explore, IEE Digital Library., 13, (1968).
4. Thomas Schon, Dept. Electrical Eng., Sweden. (2003).
5. G.E. Hovland et.al, Science Direct, Elsevier 13, 1341–1355(2005).