From an AP story by John Carucci headlined “Joni Mitchell honored with Gershwin Prize at tribute concert”:

When Joni Mitchell finally took the stage near the end of an all-star tribute concert honoring her as this year’s recipient of the Library of Congress Gershwin Prize for Popular Song, she opted to perform a cover rather than one of her own songs.

The 79-year-old music legend leaned against the piano Wednesday as she crooned a sultry version of “Summertime,” the popular tune from George Gershwin’s “Porgy and Bess,” an appropriate choice since the award was named after the composer.