Change bibliography sort order

I have come up against a problem I can’t solve on the sort order. I have two references by different authors with the same surname but different initials. The references are both from the same edited book. EndNote is listing them as ref a and ref b so doesn’t seem to be taking the initial into account. I can’t find anywhere in the style editor to alter this. Does anyone have any solutions for this?


You should look at (In Endnote, edit>output styles>style you are using) and make sure the Ambiguous Citations setting reflect the need to include initials.  See attached example. 


That did it. Thank you very much.