There are no examples for referencing either of these format types in the APA Publication Manual or in the APA Style Blog. There is, however, a reference to letters to the editor in the first chapter of the Publication Manual. Here, the manual refers to letters as 'Other Types of Articles' (American Psychological Association, 2010, p.11).

With this in mind, we suggest you reference both of these formats as you would reference journal articles. You can insert [letter to the editors] or [editorial] in square brackets, after the title. With the rest of the reference, it will enable your reader to track back to the original article.

As always, please consult your supervisor or lecturer for confirmation that this method of referencing letters to the editor or editorials is acceptable to them before you submit your final work.