%0 Journal Article %A Anastasia A. Myachkova %A Alexander N. Pechen %T Some Controllable and Uncontrollable Degenerate Four-Level Quantum Systems %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 2023 %P 237-251 %V 321 %I mathdoc %U http://geodesic.mathdoc.fr/item/TM_2023_321_a15/ %G ru %F TM_2023_321_a15