^"U.S. Indoor Open readies for opening round today". The Sunday Times (Delmarva). February 14, 1971. p. C-1 – via Newspapers.com. A field of 48 players representing 19 nations will vie today for $50,000 prize money in the second annual National Indoor Open Tennis Championships. Action gets underway this afternoon at 1 at the Wicomico Youth and Civic Center.