A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007

Quoting accurately and avoiding plagiarism
Quotations
Part III. Style 20 spelling

This chapter offers general guidelines for presenting quotations. Although all of the examples are in English, the guidelines also apply to quotations from other languages (see also 22.2.1).

Quoting directly from a source is just one of several options for representing the work of others in your paper; for a discussion of the alternatives and when to use them, see 7.4. Whichever option you choose, you must cite the source of the words or ideas. Chapter 15 provides an introduction to citation practices, and the following chapters describe two common citation styles (chapters 16 and 17, bibliography style; chapters 18 and 19, reference list style).

If you are writing a thesis or a dissertation, your department or university may have specific requirements for presenting quotations, which are usually available from the office of theses and dissertations. If you are writing a class paper, your instructor may also ask you to follow certain principles for presenting quotations. Review these requirements before you prepare your paper. They take precedence over the guidelines suggested here. For style guides in various disciplines, see the bibliography.

If your dissertation will be submitted to an external dissertation repository, you may need to obtain formal permission from copyright holders for certain types of quotations. See chapter 4 of the Chicago Manual of Style, 15th edition (2003).

25.1 Quoting accurately and avoiding plagiarism

Accurate quotation is crucial to the scholarly enterprise, so you must

use the most reliable edition available

transcribe the words exactly as they are in the original, or modify them only as described in 25.3

accurately report the source in your bibliography or reference list (see chapters 16 and 18) so that readers can consult it for themselves

The ethics of scholarship also require that whenever you quote words, tables, graphics, or data from a source, you clearly indicate what you borrowed and from where, using the appropriate citation style (see chapter 15). If you do not, you risk a charge of plagiarism. But even if you do cite a source accurately, you still risk a charge of plagiarism if you use the exact words of the source but fail to identify them as a quotation in one of the ways described in 25.2. For a fuller discussion of plagiarism, see 7.9.