How to get the last occurrence of a field

Hi,

I have a simple query that returns two fields. I need to modify that query so that it only returns the last or highest number for each pair of fields.

It's easier to show than explain. Here's my query:

SELECT WONum, OpNum
FROM tblHistory
ORDER BY WONum, OpNum

It returns something like this:

WONum OpNum
1396026 40.00
1396026 90.00
1396026 90.00
1396026 120.00
1427600 130.00
1456392 120.00
1456392 130.00
1458018 230.00
1458018 280.00
1460224 40.00
1460224 80.00

I need it to return:
WONum OpNum
1396026 120.00
1427600 130.00
1456392 130.00
1458018 280.00
1460224 80.00

Just the last row of each WONum, OpNum pair