ref. books   Giorgio C. Buttazzo, “Hard Realtime Computing Systems: Predictable
 Scheduling Algorithms and Applications (RealTime Systems Series)”, Springer
 Verlag Telos, 2nd Edition, 2004.
 Phillip A. Laplante, “RealTime Systems Design and Analysis”, WileyIEEE
 Press, 3rd Edition, 2004.
 Jane W. S. Liu, “RealTime Systems”, Prentice Hall, 1st Edition, 2000.
