Group By - Return single rows

Hi all.

I have the following query:

Select FrgnName, dscription, Sum(Quantity) 'Antall' from INV1 A, OINV B, OITM C

where A.DocEntry = B.DocEntry and C.ItemCode = A.ItemCode and B.DocDate = [%0]

group by Frgnname, dscription with Rollup

order by FrgnNAme

Can someone please explain how to get this query to return only one row for each data. Now it returns 2 rows for each instance of data.

I guess it is the GROUP BY function that is the reason, but how to avoid this from happening?

Thanks and regards, Runar.