Fixes some minor documentation issues (approximation algorithm subpac…

…kage) (#2481)

Thank you!

networkx/algorithms/approximation/dominating_set.py

@@ -5,14 +5,14 @@
 #   BSD license.
 """Functions for finding node and edge dominating sets.
 
-A *`dominating set`_[1] for an undirected graph *G* with vertex set *V*
+A `dominating set`_ for an undirected graph *G* with vertex set *V*
 and edge set *E* is a subset *D* of *V* such that every vertex not in
-*D* is adjacent to at least one member of *D*. An *`edge dominating
-set`_[2] is a subset *F* of *E* such that every edge not in *F* is
+*D* is adjacent to at least one member of *D*. An `edge dominating set`_
+is a subset *F* of *E* such that every edge not in *F* is
 incident to an endpoint of at least one edge in *F*.
 
-.. [1] dominating set: https://en.wikipedia.org/wiki/Dominating_set
-.. [2] edge dominating set: https://en.wikipedia.org/wiki/Edge_dominating_set
+.. _dominating set: https://en.wikipedia.org/wiki/Dominating_set
+.. _edge dominating set: https://en.wikipedia.org/wiki/Edge_dominating_set
 
 """
 from __future__ import division

networkx/algorithms/approximation/independent_set.py

@@ -14,7 +14,7 @@
 As such, it is unlikely that there exists an efficient algorithm for finding
 a maximum independent set of a graph.
 
-http://en.wikipedia.org/wiki/Independent_set_(graph_theory)
+`Wikipedia: Independent set <http://en.wikipedia.org/wiki/Independent_set_(graph_theory)>`_
 
 Independent set algorithm is based on the following paper:
 

networkx/algorithms/approximation/matching.py

@@ -7,7 +7,7 @@
 Given a graph G = (V,E), a matching M in G is a set of pairwise non-adjacent
 edges; that is, no two edges share a common vertex.
 
-http://en.wikipedia.org/wiki/Matching_(graph_theory)
+`Wikipedia: Matching <http://en.wikipedia.org/wiki/Matching_(graph_theory)>`_
 """
 #   Copyright (C) 2011-2012 by
 #   Nicholas Mancuso <nick.mancuso@gmail.com>