2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/61719We consider transformations preserving certain linear structure in Grassmannians and give some generalization of the Fundamental Theorem of Projective Geometry and the Chow Theorem [Ch]. It will be exploited to study linear $(k,n-k)$-involutions, $1<k<n-1$. The analogy of the well-known J. Dieudonné and C. E. Rickart result will be obtained.26 pagesRings and AlgebrasGroup Theory14M15, 14L35, 20G15, 51N30text