%0 Journal Article %A V. A. Strauss %T Models of self-adjoint and unitary operators in Pontryagin spaces %J Contemporary Mathematics. Fundamental Directions %D 2022 %P 522-552 %V 68 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMFD_2022_68_3_a7/ %G ru %F CMFD_2022_68_3_a7