ATHENS (Reuters) - The Greek financial stability council has recommended keeping Greek banks shut for the next six working days, a source with knowledge of the decision said on Sunday. Prime Minister Alexis Tsipras earlier announced a bank holiday and capital controls after Greeks responded to his surprise call for a referendum on bailout terms by pulling money out of banks. "Yes, the recommendation was for six days," the source said. (Reporting by George Georgiopoulos; writing by Matthias Williams)