Writing a book? A Thesis? A paper?
Mellel, your word processor, and Bookends, the wonderful reference manager, can help you add citations to your document, format them and automatically create a bibliography.
This trusty combo, tried and tested over more than a decade, will also allow you to use the powerful Live Bibliography feature (where your bibliography updates automatically), flexibility inserting, formatting and styling citations, and, well, dependability.
Mellel and Bookends together can help save you time and tears. Get a license for both for USD 89 instead of USD 108 when buying each separately.