http://en.wikibooks.org/wiki/Control_Systems/Poles_and_Zeros

http://en.wikipedia.org/wiki/RLC_circuit

http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=01086639

http://xbywb.tjujournals.com/Upload/PaperUpLoad/81730f8b-aaf9-4c81-979d-4c59fe59d743.pdf

http://books.google.com/books/about/Electrical_Network_Analysis_And_Synthesi.html?id=2DEft_wNLjQC

http://books.google.com/books?id=7zEbl3Zu0HgC&source=gbs_similarbooks

http://books.google.com/books?id=_Xn8OJTlveIC&source=gbs_similarbooks

http://www.ece.uci.edu/docs/hspice/hspice_2001_2-229.html

http://www.dspguide.com/CH32.PDF

http://www.google.com/url?sa=t&rct=j&q=%D8%B4%D8%A8%DA%A9%D9%87+%D8%B3%D9%88%D8%AF%D9%87+%D8%AF%D8%B1+%D9%85%D8%AF%D8%A7%D8%B1%D9%87%D8%A7%DB%8C+%D8%A7%D9%84%DA%A9%D8%AA%D8%B1%DB%8C%DA%A9%DB%8C&source=web&cd=1&ved=0CEsQFjAA&url=http%3A%2F%2Fwww.pnu.ac.ir%2Fportal%2FFile%2FShowFile.aspx%3FID%3D244a4f98-11fe-418d-9a07-b795600d6cd2&ei=FYbUT9GfBM6S0QX2tZH_Aw&usg=AFQjCNEmT84o_rk05bW0GAGjLyIxl9gtPQ