References for Rotating Machinery, Magnetic Interface
1. D. Hanselman, Brushless Motors: Magnetic Design, Performance, and Control of Brushless DC and Permanent Magnet Synchronous Motors, E-Man Press LLC, pp. 231-256, 2012
2. P. Krause, O. Wasynczuk, S. Sudhoff and S. Pekarek, Analysis of Electric Machinery and Drive Systems, 3rd ed., Wiley-IEEE Press, pp. 86-115, 2013.