Reference(s):
1. Basic electrical engineering, (an iso 9001: 2008 company), S. Chand & company pvt. ltd. ram nagar, new delhi – 110 055.
2. Electrical installation work, Seventh edition 2011, The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK 30 Corporate Drive, Suite 400, Burlington, MA 01803, USA First published 1992.
3. Basic electrical engineering (M. Tech)., 2005, (El. Machines) Ph.D. S.G. TARNEKAR B.E. (Hons), (Electrical Power Systems) Former Professor & Head, Electrical Engineering Department, National Institute of Technology, Nagpur.
4. Electricity, magnetism and light, copyright 2002, Wayne M. Saslow.
5. Basic electrical engineering, 2007, 2006, 2004 New Age International (P) Ltd., Published by New Age International (P) Ltd.
6. Introduction to electrical power systems, 2008 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Published by John Wiley & Sons, Inc.