A tribute to American and Greek soprano Maria Callas took place Monday at Lotte Concert Hall. The concert, titled “The Best Sopranos” brought together five sopranos, whom the artistic director Ha Man-taek of the concert and CEO of Korea ARTS Group, said “are the best sopranos to me, even though they are so far less-well known to the world.” The sopranos Park Mi-ja, Kim Ra-hee, Shin Eun-hye,.