Higman-Sims 群(英语:Higman-Simsgroup) H S {\displaystyle HS} ; McLaughlin 群(英语:McLaughlin group) M c L {\displaystyle McL} ; Held 群(英语:Held group) H e {\displaystyle
Association of America: 198, 1994, ISBN 0-88385-028-1, MR 1311249 Higman, Graham, The units of group-rings, Proceedings of the London Mathematical Society, Second