Why do authors usually put a reference section at the end of a book when they are not referenced throughout the entire book?

Question

In the references list (usually at the end of a book), I've noticed that authors like to include references to other materials. However these materials are not so-called "referenced" or "linked" at all throughout the entire book.

I was wondering why did they put that list there? Are they required to put a list of references for materials they have referred to and adopted information from?

Per the replies, I'm actually particularly interested in: Do we have to inform the authors of those books/materials, that we have the title of their books in our "bibliography" section ?

Answer 1

Usually a writer will include books that they either read or referred to as part of their research for their own book. Even though they may not quote specific passages from the original source, they are making sure that the reader knows that they had to seek additional information on one or more topics within their own book. They are not necessarily "required" to do this, but it is a good practice, just in case someone challenges you later and asks how you knew something about which you wouldn't normally have any knowledge.

Answer 2

Sounds like maybe you're working through the difference between a Works Cited page and a Bibliography.

Works Cited pages are, as the title suggests, lists of the sources actually cited in the work. Bibliographies include all the sources the author consulted in writing the new work, whether they were directly referenced or not. This is based on the idea that the books contributed to the author's understanding of the topic, even if they weren't directly used.

Different fields have different conventions re. whether to use Works Cited or Bibliography.

Answer 3

If a writer has written a historical, they will frequently add references to works about the time period or subject matter. I've seen this too with nonfictions about a certain subject matter, such as Stephen King's "Danse Macabre" (which is about the horror fiction/movie industry).

Heck, I've even seen some writers write stuff like "Please don't write me with x correction or whatever" or instructions to send inquiries to their agent or publisher. Writers don't want questions about how they wrote a book, so the references is there so if we want we can look up such information without bothering the writer.