YouTube is chock full of her performances, including concerts that show off her greatest hits (Tokyo 1980! United Nations 1978!). But if you learn some cyrillic, the rarities are buried in there too, including her non-opera work that shows off her dynamic range and musicianship. Check out the Moscow Cantata—which she sang exactly once—for her sensitive arias, but stay for the blistering duet conclusion (so nice they did it twice!).