Fix docs

Author: ddomingof

README.rst

@@ -42,7 +42,7 @@ Generates the regularised Laplian kernel of a given graph.
 References
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 .. [1] Picart-Armada, S., *et al.* (2017). `Null diffusion-based enrichment for metabolomics data
-<https://doi.org/10.1371/journal.pone.0189012>`_. *PloS one* 12.12.
+   <https://doi.org/10.1371/journal.pone.0189012>`_. *PloS one* 12.12.
 
 Disclaimer
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