Citeulike is a free service for managing and discovering scholarly references.
EndNote Basic is the free version of the popular reference software. Features storage for up to 50,000 references, the 20 most popular bibliographic styles, and 2GB of file storage.
Mendeley is a free reference manager and academic social network that can help you organize your research, collaborate with others online, and discover the latest research in your field
ReadCube is a free desktop and browser-based program for managing, annotating, and accessing academic research articles.
RefWorks is web-based bibliographic software that enables you to organize your research, include citations while you write your paper, build a bibliography in a variety of formats, import references from many data sources, and create bibliographies in different document formats (Word, RTF, HTML, etc.).
Zotero collects all your research in a single, searchable interface. You can add PDFs, images, audio and video files, snapshots of web pages. Zotero automatically indexes the full-text content of your library, enabling you to find exactly what you're looking for.
The in-text reference that gives brief details (author, date, page) of the source you are quoting or referring to. This citation corresponds with the full details of the work (title, publisher, etc) given in your reference list or bibliography, so that the reader can identify and/or find the source.
A list of references at the end of your paper that includes the full information for your citations so that the reader can easily identify and retrieve each work (journal articles, books, webpages, etc). Your reference list contains all the items you have cited or directly quoted from.
A list of works you have consulted for your paper, but not cited in the Reference List. Works should be listed in alphabetical order by author and laid out in the same way as items in your reference list. If you can cite from every work you consulted, you will only need a reference list.
Always check the guidance you are given for your research paper to find out if you are expected to submit work with a reference list and a bibliography.