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    ".. [1] Nicholas J. Higham and Francoise Tisseur (2000),",
    "       \"A Block Algorithm for Matrix 1-Norm Estimation,",
    "       with an Application to 1-Norm Pseudospectra.\"",
    "       SIAM J. Matrix Anal. Appl. Vol. 21, No. 4, pp. 1185-1201.",
    "",
    ".. [2] Awad H. Al-Mohy and Nicholas J. Higham (2009),",
    "       \"A new scaling and squaring algorithm for the matrix exponential.\"",
    "       SIAM J. Matrix Anal. Appl. Vol. 31, No. 3, pp. 970-989."
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