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    ".. [1] AC Kak, M Slaney, \"Principles of Computerized Tomographic",
    "       Imaging\", IEEE Press 1988.",
    ".. [2] B.R. Ramesh, N. Srinivasa, K. Rajgopal, \"An Algorithm for Computing",
    "       the Discrete Radon Transform With Some Applications\", Proceedings of",
    "       the Fourth IEEE Region 10 International Conference, TENCON '89, 1989"
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