ot on ). ▁Since ▁then , ▁K ova č ič ek ▁be ars ▁the ▁char ism ▁of ▁the ▁most ▁s oph istic ated ▁female ▁rock ▁vocal ▁in ▁Cro atia . ▁ ▁In ▁the ▁mid - 1 9 7 0 s , ▁she ▁performed ▁in ▁rock ▁opera ▁" G ri čka ▁v je št ica " ▁by ▁I v ica ▁Kra ji ć , ▁Kar lo ▁Met iko š ▁and ▁Mil jen ko ▁Pro h aska ▁in ▁the ▁Zag reb ▁Com edy ▁Theater , ▁sang ▁with ▁Y ug oslav ▁jazz ▁rock ▁selection ▁and ▁took ▁part ▁in ▁the ▁recording ▁of ▁album ▁" Pop " ▁by ▁T ih om ir ▁" Pop " ▁As an ović , ▁which ▁was ▁released ▁in ▁ 1 9 7 6 ▁by ▁the ▁record ▁company ▁Jug ot on . ▁At ▁that ▁time , ▁her ▁name ▁was ▁mentioned ▁in ▁rock ▁and ▁jazz ▁music , ▁she ▁performed ▁on ▁every ▁major ▁bl ues ▁and ▁soul ▁ensemble , ▁received ▁many ▁awards ▁and ▁was ▁proc laimed ▁the ▁best ▁female ▁vocal ▁in ▁Y ug oslav ia . ▁In ▁ 1 9 7 6 , ▁she ▁founded ▁the ▁rh ythm , ▁bl ues , ▁rock , ▁and ▁soul ▁band ▁Z den ka ▁Express , ▁with ▁whom ▁she ▁performed ▁the ▁song ▁" H allo , ▁Mr . ▁El ton ▁John " ▁ ▁which ▁is ▁on ▁the ▁concert ▁compilation ▁of ▁the ▁BO OM ▁festival ▁' 7 6 . ▁( pub lished ▁by ▁P GP - RT B ). ▁In ▁ 1 9 7 8 , ▁K ova č ič ek