Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What is the USN 2013 ranking with a BW 2013 ranking less than 1000, a Forbes 2011 ranking larger than 17, and a CNN 2011 ranking less than 13?

### Inputs:
table_name: table, columns: ['Location (State, City)', 'USN 2013', 'BW 2013', 'Forbes 2011', 'Ec 2013', 'FT 2011', 'AE 2011', 'CNN 2011', 'BI 2013', 'ARWU 2012']

### Response:
SELECT SUM USN 2013 FROM table WHERE BW 2013 < 1000 AND Forbes 2011 > 17 AND CNN 2011 < 13