Lee, WCY, Ziemer, R.E., Ovan, M. Mandyam, G.D. "Personal and Office The Electrical Engineering Handbook Ed. Richard C. Dorf Boca raton crc Press llc. 2000Lee, W.C.Y., Ziemer, R.E., Ovan, M. Mandyam, G.D. “Personal and Office” The Electrical Engineering Handbook Ed. Richard C. Dorf Boca Raton: CRC Press LLC, 2000