High torque micro slice motor using a multipole ring magnet - ScienceDirect
Magnac Bourg Magnet Lodestone Île De France (87) France Fridge Magnet Souvenir I Love Gift - Fridge Magnets - AliExpress
Large Size Zn Plating Ring Neodymium Magnet with Super Strong Force for Magnetic Rod/Bar/Separator - China Permanent Magnet, Rare Earth Magnet | Made-in-China.com