ug oslav - pub lished ▁Encyc lo pa edia ▁of ▁Ch ess ▁Open ings ▁( E CO ), ▁which ▁appeared ▁in ▁ 1 9 7 4 . ▁K eres ▁also ▁co - f ounded ▁the ▁R iga ▁magazine ▁Sh akh mat y . ▁ ▁K eres ▁made ▁many ▁important ▁contributions ▁to ▁opening ▁theory . ▁Perhaps ▁best - known ▁is ▁the ▁K eres ▁Att ack ▁against ▁the ▁Sch even ingen ▁Vari ation ▁of ▁the ▁Sic ilian ▁Def ence ▁( 1 . e 4 ▁c 5 ▁ 2 . N f 3 ▁d 6 ▁ 3 . d 4 ▁cx d 4 ▁ 4 . N x d 4 ▁N f 6 ▁ 5 . N c 3 ▁e 6 ▁ 6 . g 4 ), ▁which ▁was ▁successfully ▁introduced ▁against ▁E f im ▁Bog oly ub ov ▁at ▁Sal zburg ▁ 1 9 4 3 , ▁and ▁remains ▁an ▁important ▁line . ▁An ▁original ▁system ▁on ▁the ▁Black ▁side ▁of ▁the ▁Cl osed ▁R uy ▁L ope z ▁( 1 . e 4 ▁e 5 ▁ 2 . N f 3 ▁N c 6 ▁ 3 . B b 5 ▁a 6 ▁ 4 . B a 4 ▁N f 6 ▁ 5 . 0 - 0 ▁Be 7 ▁ 6 . Re 1 ▁b 5 ▁ 7 . B b 3 ▁d 6 ▁ 8 . c 3 ▁ 0 - 0 ▁ 9 . h 3 ▁Na 5 ▁ 1 0 . B c 2 ▁c 5 ▁ 1 1 . d