Same author has published more than one work in the same year
In these cases the citations should include letters, following the years of publication, to differentiate between the references.
The letters are also used in the reference list (but NOT the bibliography if you have a separate bibliography) at the end of your work. This allows the reader to identify the exact reference which you have cited.
Therefore, where two or more items share the same author and year of publication the procedure is as follows:
Arrange the items in your reference list alphabetically by title, as this will be the first element of alphabetical difference between them.
Brown, C. (2014). Casting a long shadow ...
Brown, C. (2014). Famous in ...
Brown, C. (2014). Referencing and life ...
Having done this, assign a letter to each year of publication, in the order in which you have arranged them in your list.
Brown, C. (2014a). Casting a long shadow ...
Brown, C. (2014b). Famous in ...
Brown, C. (2014c). Referencing and life ...
Make sure that the correct letters are assigned to the years of publication in the citations in your text so that the reader is directed to the correct reference in your list.
Note that this means that (2014a) will not necessarily be cited first in your text.
(The above instructions also apply where authors with the same surname and initials have published items in the same year.)