What do I do with a source within a source (indirect reference)?
If you want to refer to a source that is included in another source, we recommend that you try to track down the original source. If you find it, you can then just cite it following the normal APA rules.
If you cannot find that original source, you should cite it through the source that mentioned it. This is called making an indirect reference or citing a secondary source.
Within your text, you then need to mention both authors.
Example: Driessen (in Swaen, 2014) uses three methods.
If one author has quoted another author, you need to add “as cited.”
Example: Driessen (in Swaen, 2014) describes three methods.