Figure 11 from Design and dynamic study of a 6 kW external rotor permanent magnet Brushless DC motor for electric drivetrains | Semantic Scholar
Comparing Slotted vs Slotless Brushless DC Motors
Design of Brushless Permanent-magnet Machines - J. R. Hendershot, Timothy John Eastham Miller - Google Books
Amazon.com: Design of Brushless Permanent-Magnet Motors (Monographs in Electrical and Electronic Engineering): 9780198593898: Hendershot Jr., J. R., Miller, T. J. E.: Books
Design and prototyping methods for brushless motors and motor control | Semantic Scholar