%0 Journal Article %A M. F. Raţă %A A. G. Russu %T On some properties of systems, complete with respect to expressibility, of formulas in the G\"odel--L\"ob provability logic %J Diskretnaya Matematika %D 2000 %P 63-82 %V 12 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/DM_2000_12_4_a5/ %G ru %F DM_2000_12_4_a5