9 0 ▁and ▁No . ▁ 6 ▁in ▁ 1 9 9 2 . ▁George ▁Ro ch berg ▁( 1 9 1 8 – 2 0 0 5 ) ▁Seven ▁quart ets : ▁The ▁sixth ▁quart et ▁includes ▁a ▁set ▁of ▁variations ▁on ▁P ach el bel ' s ▁Can on ; ▁the ▁second ▁includes ▁a ▁sop rano ▁part ▁with ▁texts ▁by ▁R il ke ; ▁the ▁sevent h ▁includes ▁a ▁bar it one ▁part ▁to ▁texts ▁by ▁his ▁late ▁son . ▁String ▁Quart et ▁No . ▁ 3 ▁is ▁well ▁known ▁for ▁its ▁supposed ly ▁ne o - rom antic ▁est h etic . ▁S ven - E rik ▁B äck ▁( 1 9 1 9 – 1 9 9 4 ): ▁Four ▁( 1 9 4 5 , ▁ 1 9 4 7 , ▁ 1 9 6 2 , ▁ 1 9 8 4 ). ▁Ph yll is ▁G um mer ▁( 1 9 1 9 – 2 0 0 5 ): ▁Four ▁string ▁quart ets . ▁Leon ▁Kirch ner ▁( 1 9 1 9 – 2 0 0 9 ): ▁Four ▁( 1 9 4 9 , ▁ 1 9 5 8 , ▁ 1 9 6 7 , ▁ 2 0 0 7 ); ▁the ▁third , ▁which ▁includes ▁a ▁t ape ▁part , ▁won ▁the ▁Pul itzer ▁Prize ▁for ▁Music , ▁ 1 9 6 7 . ▁Mie cz ys ław ▁Wein berg ▁( 1 9 1 9 – 1 9 9 6 ): ▁Se vent een