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_31321 ( "SAR No." real, "Builder" text, "Year" real, "Works No." real, "Firebox" text, "Driver Diameter" text )

### Question ###
What are the works numbers where the year is 1929 and the driver diameter is 60'/1520mm?

### Accurate SQL ###

SELECT "Works No." FROM table_31321 WHERE "Year" = '1929' AND "Driver Diameter" = '60"/1520mm'