Question: Margaret "Maggie" Black (March 31, 1930 – May 11, 2015) was a ballet teacher who taught in New York City during the 1970s and 1980s, she coached dancers such as which American ballerina, who joined the New York City Ballet in 1968 at age fifteen, at the invitation of George Balanchine?
Sentence (from "Patricia Wilde"): Her biography "Wilde Times: Patricia Wilde, George Balanchine and the Rise of New York City Ballet", by Joel Lobenthal was published in 2015 by the University Press of New England.
Relevant evidence: No