Answered By: Last Updated: Jan 11, 2019 Views: 7
This is a great question. An answer to this question and more can be found in the MLA Handbook for Writers of Research Papers, which can be found at the reference desk.
The manual is unfortunately not available online.
If you are citing a source that is found within another source, use the abbreviation "qtd. in." Here is an excellent example from the Writing Center at the University of Maryland.
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