Frank Sinatra
From Tardis Wiki, the free Doctor Who reference
Francis Albert "Frank" Sinatra was an American singer and actor in the 20th century. The Doctor was on close personal terms with him, using a cabin owned by him to hold a party with Albert Einstein and Father Christmas. In 1952, the Eleventh Doctor and Sinatra were both present at a Hollywood party, the two performing a duet. (DW: A Christmas Carol)