There are two primary forms of citation in the harvard style dependent upon whether the reference is used as a noun or parenthetically. Additionally, where there are more than two authors, all authors are listed in the first citation and in subsequent citations just the first author's name followed by `et al.' is used. The following example from Pitson (1978) illustrates these points.
The major improvement concerns the structure of the interview (Ulrich & Trumbo 1965, p. 112) .... Later reports (Carlson, Thayer, Mayfield & Peterson 1971) record greatly increased interviewer reliability for structured interviews. Wright (1969, p. 408) comments that `undoubtedly interviewer skill is directly related to the validity, quantity and quality of the interview output', and this would suggest some sort of interviewer training is called for. Rowe (1960), for example, found that trained interviewers are better able to evaluate applicants with some measure of reliability. In addition Wexley, Sanders & Yukl (1973) showed that by extensive interviewer training all significant contrast effects could be eliminated. The results of the 1971 study (Carlson et al. 1971) are still relevant, but efforts to ....
To facilitate using a citation as a noun a new command
citeasnoun has been created which has the same syntax as the
cite command except that multiple citations are not
permitted.
The effect of this command is that
As \citeasnoun{btxdoc} and \citeasnoun[Annex~B]{latex} describe \ldotsproduces
As Patashnik (1988) and Lamport (1986, Annex B) describe ...whereas
The \BibTeX\ \cite{btxdoc} and \LaTeX\ \cite[Annex~B]{latex} manuals \ldotsproduces
The BibTeX (Patashnik; 1988) and LATEX (Lamport; 1986, Annex B) manuals ...A second new command
\possessivecite{latex} description of this feature is \ldotsproduces
Lamport's (1986) description of this feature is ...A third new command
\BibTeX\ manuals \citeaffixed{latex,btxdoc}{e.g.} describe \ldotsproduces
BibTeX manuals (e.g. Lamport; 1986; Patashnik; 1988) describe ...