1. Oak Ridge National Laboratory (2009) Advanced brush technology for DC motors. http://peemrc.ornl.gov/projects/emdc3.jpg
2. Arof S, Jalil JA, Yaakop NM, Mawby PA, Arof H (2014) Series motor four quadrants drive Dc chopper. Part1: Overall. In: IEEE International conference on power electronics
3. Arof S, Noorsal E, Mawby PA, Arof H (2020) Series motor four quadrants drive DC chopper for DC drive electric vehicle. Part 7: Resistive braking. In: International scientific forum (ISF2019), Melaka, Malaysia. eISBN: 978-967-10842-1-2
4. Arof S, Noorsal E, Mawby PA, Arof H (2020) Series motor four quadrants drive DC chopper for DC drive electric vehicle. Part 6: Regenerative braking. In: International scientific forum (ISF2019), Melaka, Malaysia. eISBN: 978-967-10842-1-2
5. Arof S, Diyanah NHN, Mawby PA, Arof H, Noorsal E (2021) Series motor four quadrants drive DC chopper. Part 3: Field weakening mode. IOP Conf Ser Mater Sci Eng 1127(1):012028. https://doi.org/10.1088/1757-899X/1127/1/012028