Celso Albelo
He has sung leading roles in many opera houses including Teatro alla Scala ( Milan ) , the Royal Opera House ( London ) , Teatro La Fenice ( Venice ) . 
<triplet> Teatro alla Scala <subj> opera house <obj> instance of <subj> Milan <obj> located in the administrative territorial entity <triplet> Royal Opera House <subj> opera house <obj> instance of <subj> London <obj> located in the administrative territorial entity