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  "references": [
    ".. [1] Rizzo, Szekely \"Energy distance.\" Wiley Interdisciplinary Reviews:",
    "       Computational Statistics, 8(1):27-38 (2015).",
    ".. [2] Szekely \"E-statistics: The energy of statistical samples.\" Bowling",
    "       Green State University, Department of Mathematics and Statistics,",
    "       Technical Report 02-16 (2002).",
    ".. [3] \"Energy distance\", https://en.wikipedia.org/wiki/Energy_distance",
    ".. [4] Bellemare, Danihelka, Dabney, Mohamed, Lakshminarayanan, Hoyer,",
    "       Munos \"The Cramer Distance as a Solution to Biased Wasserstein",
    "       Gradients\" (2017). :arXiv:`1705.10743`."
  ],
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