user: Question: When the engine Ford Cosworth DFV 3.0 V8 has a chassis of M23 and in rounds 14-15, what is its Tyre?
Columns: ['Constructor', 'Chassis', 'Engine', 'Tyre', 'Driver', 'Rounds']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Lotus - Ford', '72E 76', 'Ford Cosworth DFV 3.0 V8', 'G', 'Ronnie Peterson', 'All']
SQL:

assistant: SELECT "Tyre" FROM "Table" WHERE "Rounds" = '14-15' AND "Engine" = 'Ford Cosworth DFV 3.0 V8' AND "Chassis" = 'M23';