Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_59 ( tournament VARCHAR )

### Question ###
What is 1994, when 1991 is 'QF', and when Tournament is 'Australian Open'?

### Accurate SQL ###

SELECT 1994 FROM table_name_59 WHERE 1991 = "qf" AND tournament = "australian open"