At the end of your writing, you should include a list of ALL the references you have cited in your document.
In the Harvard Style, sources that are not cited in the text but are relevant to the subject may be listed separately as a bibliography. The same method of presentation is used for both a list of references and a bibliography.
The Reference List is arranged alphabetically by author, and thereafter chronologically, starting with the earliest date.
For example:
Jones, AB 2000,…
Jones, B 1995, …
Smith, AK 1990, …
Smith, AK 1995, …
Stein, B 2003 …
Stein, B & Reynolds, JS 1995, …
Stein, B & Reynolds, JS 2000, …
Style manual for authors, editors and printers 2002, …
Yarbro, CH, Frogge, MH, Goodman, M & Groenwald, SL 2000, …
Young, JC 1988a, …
Young, JC 1988b, …
Source: Charles Darwin University Library, Library & Information Access January 2007 Adapted from RMIT University Library: Referencing gui (http://www.cdu.edu.au/library/infolit/tutorials.html#Referencing)