On finite linear groups stable under Galois operation. Khrebtova, Ekaterina, Malinin, Dmitry (2009) Acta Mathematica Academiae Paedagogicae Nyí regyháziensis. New Series [electronic only]
On perfect isometries and isotypies in finite groups. Paul Fong, Morton E. Harris (1993) Inventiones mathematicae
On the projective characters in characteristic 2 of the groups S u z ( 2 m ) and S p 4 ( 2 n ) Leonard Chastkofsky, Walter Feit (1980) Publications Mathématiques de l'IHÉS