user: Question: On what date was Richmond playing as an away team?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Melbourne', '10.11 (71)', 'St Kilda', '10.16 (76)', 'MCG', 30581.0, '13 July 1968']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Away team" = 'Richmond';