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    ".. [1] M. Sullivan and M. Sullivan, III, \"Algebra and Trigonometry,",
    "   Enhanced With Graphing Utilities,\" Prentice-Hall, pg. 318, 1996.",
    "",
    ".. [2] G. Strang, \"Linear Algebra and Its Applications, 2nd Edition,\"",
    "   Academic Press, pg. 182, 1980."
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