Update citing.rst

Author: oesteban

docs/citing.rst

@@ -226,15 +226,15 @@ Posters
 -------
 
 * Organization for Human Brain Mapping 2018
-  (`Abstract <https://ww5.aievolution.com/hbm1801/index.cfm?do=abs.viewAbs&abs=1321>`_;
-  `PDF <https://files.aievolution.com/hbm1801/abstracts/31779/2035_Markiewicz.pdf>`_)
+  (`Abstract <https://ww5.aievolution.com/hbm1801/index.cfm?do=abs.viewAbs&abs=1321>`__;
+  `PDF <https://files.aievolution.com/hbm1801/abstracts/31779/2035_Markiewicz.pdf>`__)
 
 .. image:: _static/OHBM2018-poster_thumb.png
    :target: _static/OHBM2018-poster.png
 
 * Organization for Human Brain Mapping 2017
-  (`Abstract <https://ww5.aievolution.com/hbm1701/index.cfm?do=abs.viewAbs&abs=4111>`_;
-  `PDF <https://f1000research.com/posters/6-1129>`_)
+  (`Abstract <https://ww5.aievolution.com/hbm1701/index.cfm?do=abs.viewAbs&abs=4111>`__;
+  `PDF <https://f1000research.com/posters/6-1129>`__)
 
 .. image:: _static/OHBM2017-poster_thumb.png
    :target: _static/OHBM2017-poster.png
@@ -243,7 +243,7 @@ Presentations
 -------------
 
 * Organization for Human Brain Mapping 2018
-  `Software Demonstration <https://effigies.github.io/fmriprep-demo/>`_.
+  `Software Demonstration <https://effigies.github.io/fmriprep-demo/>`__.
 
 .. include:: license.rst