Projective symplectic geometry on regular subspaces; Grassmann spaces   over symplectic copolar spaces
  We construct Grassmann spaces associated with the incidence geometry of regular and tangential subspaces of a symplectic copolar space, show that the underlying metric projective space can be recovered in terms of the corresponding adjacencies on so distinguished family of k-subspaces (geometrical dimension of the space being not 2k+1), and thus we prove that bijections which preserve the adjacency are determined by automorphisms of the underlying space. 
M. Pra\.zmowska, K. Pra\.zmowski, M. \.Zynel
math.CO math.MG