Bernard Ładysz
... that Bernard Ładysz, a bass-baritone who performed in world premieres of Krzysztof Penderecki's music in Hamburg and in Salzburg, was the only Polish singer to appear with Maria Callas?
... that <b id="mwAl8"><a href="./Bernard_Ładysz" id="mwAmA" rel="mw:WikiLink" title="Bernard Ładysz">Bernard Ładysz</a></b>, a <a href="./Bass-baritone" id="mwAmE" rel="mw:WikiLink" title="Bass-baritone">bass-baritone</a> who performed in world premieres of <a href="./Krzysztof_Penderecki" id="mwAmI" rel="mw:WikiLink" title="Krzysztof Penderecki">Krzysztof Penderecki</a>'s music <a href="./Hamburg_State_Opera" id="mwAmM" rel="mw:WikiLink" title="Hamburg State Opera">in Hamburg</a> and <a href="./Salzburg_Festival" id="mwAmQ" rel="mw:WikiLink" title="Salzburg Festival">in Salzburg</a>, was the only Polish singer to appear with <a href="./Maria_Callas" id="mwAmU" rel="mw:WikiLink" title="Maria Callas">Maria Callas</a>?