Views - my results show duplicates and triplicates

Hi,

I created a view for our database.  It looks great and unlike the Biblio Module, the Search and Filter functions work perfectly.  The problem is that it is duplicating the entries (results).  For example, if you run a search for Reference Type, “Audiovisual Material” it shows 4 results and one of those is a triple copy.  I noticed that other Reference Types have a double or triple copy.  I created a view before and didnt have this problem.  I also checked the content on my site to make sure that the original import was not duplicated.  And everything is fine, all of the Biblio records were only imported once.  How can I fix this?  What am I doing wrong?

Many thanks!

Esther