I have a simple reference library database based on one table.  There is a
combo box where the user is to select a topic and the publications that I
have assigned to this topic are displayed in a sub form.  The problem is that
I want the combo box to list each topic just once but it doesn't, it has an
entry for that topic for each publication.  i.e one topic is 'housing' and
there are 6 items in the library that come under this so the combo box lists'
housing' 6 times.  I have tried adding SELECT DISTINCT
to the code in the Rowsource but this doesn't do anything.  Any suggestions?
This is my Rowsource code..

SELECT DISTINCT [tblReference Libary].[Reference LibraryID], [tblReference
Libary].Topic
FROM [tblReference Libary];