%0 Journal Article %A V. Gould %A A. V. Mikhalev %A E. A. Palyutin %A A. A. Stepanova %T Model-theoretic properties of free, projective, and flat $S$-acts %J Fundamentalʹnaâ i prikladnaâ matematika %D 2008 %P 63-110 %V 14 %N 7 %I mathdoc %U http://geodesic.mathdoc.fr/item/FPM_2008_14_7_a6/ %G ru %F FPM_2008_14_7_a6