Peter, Paul - but no Mary

Mary Travers is in the hospital with a respiratory infection, so she won't be leaving on a jet plane for Sunday's concert at the Kimmel Center.

Peter Yarrow and Noel (Paul) Stookey will perform as a duo.

Those who wish to receive a refund can contact Ticket Philadelphia at 215-893-1999 or patronservices@ticketphiladelphia.org for a full refund if they so desire, says the Kimmel.