Citing quotations (Harvard style referencing)

In scientific writing, it is generally the case that you should paraphrase from sources, rather than quote directly.

If you use a direct quotation from an author, you should:

• enclose this in quotation marks 
• give the author, date and page number(s) that the quotation was taken from, in brackets.

Example:
"language is subject to change, and is not caused by unnecessary sloppiness, laziness or ignorance" (Aitchison 1981 p.67)

If the quotation is more than two lines:

• It is separated from the rest of the paragraph by one free line above and below 
• It is indented at left and right margins 
• It may be in a smaller point size 
• It is preceded by a colon  
• It does not use quotation marks
• It includes page number(s) as well as author and date.

Example:
One answer to this is that language has always been subject to change, just as everything else in the world is, and we should not feel that this is a bad thing. As Aitchison (1981 p.16) puts it:

Language, then, like everything else, gradually transforms itself over the centuries. There is nothing surprising in this. In a world where humans grow old, tadpoles change into frogs, and milk turns into cheese, it would be strange if language alone remained unaltered. In spite of this, large numbers of intelligent people condemn and resent language change, regarding alterations as due to unnecessary sloppiness, laziness or ignorance. 

Aitchison clearly sees every change in language as neither good nor bad, but inevitable...

Editing a quote

You may want to make minor changes to a direct quotation. This is possible (as long as you don't change the meaning), but you must follow the rules.

• If you omit parts of the quotation, whether from the beginning, middle or end, use an ellipsis. An ellipsis consists of three dots (...)
• If you want to insert your own words, or different words, into a quotation, put them in square brackets [ ]  
• If you want to draw attention to an error in a quotation, for example a spelling mistake or wrong date, don't correct it; write [sic] in square brackets 
• If you want to emphasise something in a quotation which is particularly relevant to your essay, put the emphasised words in italics, and state that the emphasis is your own 
• If the original has italics, state that the italics are in the original.

Example:
Language changes are natural and inevitable. As Aitchison (1981 p.16) points out, language:

gradually transforms itself over the centuries. In a world where [everything changes], it would be strange if language alone remained unaltered. In spite of this, large numbers of intelligent people condemn and resent language change.

Smith (1992 p.45), commenting on this, says: "Aitcheson [sic] appears to believe that everything changes; but this is questionable" (italics in original).