Hi,

I have set my references according to APA 6th edition.

I have 2 instances of: same author, same year, but they are shown differently.

One time without 'a' and 'b' behind the years:
(Wetenschappelijke Raad voor het Regeringsbeleid, 2012, 2012)

And one time with 'a' and 'b' behind the years:
(Raad voor het Openbaar Bestuur, 2012a, 2012b)

How is this possible within one document?
I would like this to be the same, preferably both times with 'a' and 'b' behind the years, so that the first one will also be shown as:
(Wetenschappelijke Raad voor het Regeringsbeleid, 2012a, 2012b)

but I don't know what to do to get this done automatically.

any hints are kindly appreciated!!