%0 Journal Article %A Svetlana Topalova %T STS(21) with Automorphisms of Order 3 with 3 Fixed Points and 7 Fixed Blocks %J Mathematica balkanica %D 2004 %P 215 %V 18 %N 1-2 %I mathdoc %U http://geodesic.mathdoc.fr/item/MABA_2004_18_1-2_a23/ %F MABA_2004_18_1-2_a23