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          "value": "H_+ = H + (dx - H df) df^\\dagger / ( df^\\dagger df)"
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    ".. [1] B.A. van der Rotten, PhD thesis,",
    "   \"A limited memory Broyden method to solve high-dimensional",
    "   systems of nonlinear equations\". Mathematisch Instituut,",
    "   Universiteit Leiden, The Netherlands (2003).",
    "",
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