Wikipedia:QUOTE

Quotations are a good way to comply with the no original research policy but must be used with care.

The quotation should be representative of the whole source document; editors should be very careful to avoid misrepresentation of the argument in the source.

For free or public domain material, usage of quote marks is not required by copyrights, but to avoid plagiarism; that is still wrong. Explicit quotes must be used to provide clear attribution of wording to the original author(s). At a minimum the text must be attributed and given a footnote, or given a link to the original text. For copyrighted material, see below. For free or public domain material, longer quotes may often be used than would be allowed under "fair use" of copyrighted material.

Do not put quotations in italics unless the material would otherwise call for italics, such as for emphasis and the use of non-English words (see the Manual of Style). Indicate whether italics were used in the original text or whether they were added later. For example:

Now cracks a noble heart. Good night sweet prince: And flights of angels sing thee to thy rest! [emphasis added]

Quotations must always be clearly indicated as being quotations. For information regarding the use of punctuation with quotations, including the use of quotation marks within quotations, see the Manual of Style: "Quotations".

If not used verbatim, any alterations must be clearly marked, i.e.

Unexpected errors, imperfections and styles can be marked with " [sic]"—using the template {{}}— or "[emphasis in the original]", to indicate that the error is in the original source. Exceptions are trivial spelling or typographical errors that obviously do not affect the intended meaning; these may be silently corrected.

Quotations should generally be worked into the article text, so as not to inhibit the pace, flow and organization of the article. Longer quotes may need to be set apart, generally through the use of templates such as {{}} or the HTML blockquote element. Longer quotations may also be hidden in the reference (footnote) to facilitate verification by other editors without sacrificing readability.

In some instances, quotations are preferred to text. For example:

Overuse happens when:

When copyrighted text must be quoted, see the plagiarism and non-free content guidelines. Extensive quotation of copyrighted text is prohibited.

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