Question
Do you include Forewords or Introductions in bibliographic entries?
Answer
Books may contain front matter -- prefaces, forewords, introductions -- and/or back matter, like an afterword. Whether you cite these depends on a couple of things.
First, did you quote or paraphrase from those sections?
MLA
This may seem obvious to some, but it can be confusing to know which names and titles need to be documented in a citation! Especially when the authors of forewords and introductions are often named on the book cover as part of the marketing.
If you didn't use anything from these sections, you don't need to document the front/back matter at all. Just cite the overall book.
APA
Include the additional author in the reference citation, but only use the main book author for your in-text citations if you're only using the main author's content.
Example citation: Jackson, S. (with Moshfegh, O.). (2017). Dark tales. Penguin Books.
Jackson is the original author, and Moshfegh wrote the foreword for that edition. If you aren't using anything Moshfegh wrote, all your in-text citations will only mention Jackson.
Second, is the author the same as or different from the main work?
MLA
If the front matter was written by the author of the book, then you don't need to do anything special -- just cite the overall book. Your in-text citation will use whatever style those page numbers are in, though you might mention in your paper that you're using content from another part of the book than the main section. (E.g. In her introduction to a later edition of the book, the author explains...)
Jackson, Shirley. Dark Tales. Penguin Books, 2017.
But if that section was written by someone else, we need a separate citation for it. The author of that section is your leading author, and the title of the source is whatever the section is called. The book will be treated as a container, with the primary author named as a contributor.
Moshfegh, Ottessa. Foreword. Dark Tales, by Shirley Jackson, Penguin Books, 2017, pp. vii - x.
Your Works Cited would then cite both (per these examples) the Moshfegh and the Jackson citations.
APA
Example citation: Jackson, S. (with Moshfegh, O.). (2017). Dark tales. Penguin Books.
To cite something from the foreword for that example would look like:
- Narrative: Moshfegh notes the context that influenced Jackson (2017) "placeholder quote" (p. ix).
- Parenthetical: Placeholder about midcentury suburbia (Jackson, 2017, foreword by Moshfegh, p. ix).