Fix sphinx API link
@@ -166,7 +166,7 @@ It is also possible to select time range:
Getting list of available missions
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-The `~astroquery.heasarc.Heasarc.query_mission_list` method will return a list of available missions
+The `~astroquery.heasarc.HeasarcClass.query_mission_list` method will return a list of available missions
that can be queried.
.. doctest-remote-data::
