There are 2 approaches to listing all the references used when writing a document:
Bibliographies list sources alphabetically, you can also group them by topic or type of source and then list them alphabetically within each category.
A bibliography usually sits at the end of your text, but before the index if you have one. For advice on styling the references, please see our Reference lists entry.
How you use a bibliography will depend on whether you are using the documentary note or author–date referencing system.
A bibliography is optional if you are using the documentary note system because you will have cited the details of your sources in your footnotes or endnotes.
However, it is still a useful reference in many publications because it provides an alphabetical list of all sources. It also enables you to include sources you have read but did not explicitly cite in the text.
The author–date system requires a reference list for its in-text citations because it does not use footnotes or endnotes.
You can expand such a reference list into a bibliography if you’d like to include a broader range of references than those you explicitly cite.