diff --git a/docs/relay/nodes.rst b/docs/relay/nodes.rst
index 59c818da..4b2c96aa 100644
--- a/docs/relay/nodes.rst
+++ b/docs/relay/nodes.rst
@@ -3,7 +3,7 @@ Nodes
 
 A ``Node`` is an Interface provided by ``graphene.relay`` that contains
 a single field ``id`` (which is a ``ID!``). Any object that inherits
-from it have to implement a ``get_node`` method for retrieving a
+from it has to implement a ``get_node`` method for retrieving a
 ``Node`` by an *id*.
 
 
@@ -26,8 +26,8 @@ Example usage (taken from the `Starwars Relay example`_):
             return get_ship(id)
 
 The ``id`` returned by the ``Ship`` type when you query it will be a
-scalar which contains the enough info for the server for knowing it’s
-type and it’s id.
+scalar which contains enough info for the server to know its type and
+its id.
 
 For example, the instance ``Ship(id=1)`` will return ``U2hpcDox`` as the
 id when you query it (which is the base64 encoding of ``Ship:1``), and
@@ -77,7 +77,7 @@ Accessing node types
 If we want to retrieve node instances from a ``global_id`` (scalar that identifies an instance by it's type name and id),
 we can simply do ``Node.get_node_from_global_id(global_id, context, info)``.
 
-In the case we want to restrict the instnance retrieval to an specific type, we can do:
+In the case we want to restrict the instance retrieval to a specific type, we can do:
 ``Node.get_node_from_global_id(global_id, context, info, only_type=Ship)``. This will raise an error
 if the ``global_id`` doesn't correspond to a Ship type.
 
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 5de8cc6b..31a23482 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,2 +1,4 @@
+# Required library
+Sphinx==1.5.3
 # Docs template
 https://github.com/graphql-python/graphene-python.org/archive/docs.zip
diff --git a/docs/types/mutations.rst b/docs/types/mutations.rst
index 11211593..d7f590a4 100644
--- a/docs/types/mutations.rst
+++ b/docs/types/mutations.rst
@@ -10,20 +10,20 @@ This example defines a Mutation:
 
 .. code:: python
 
-import graphene
+    import graphene
 
-class CreatePerson(graphene.Mutation):
-    class Input:
-        name = graphene.String()
+    class CreatePerson(graphene.Mutation):
+        class Input:
+            name = graphene.String()
 
-    ok = graphene.Boolean()
-    person = graphene.Field(lambda: Person)
+        ok = graphene.Boolean()
+        person = graphene.Field(lambda: Person)
 
-    @staticmethod
-    def mutate(root, args, context, info):
-        person = Person(name=args.get('name'))
-        ok = True
-        return CreatePerson(person=person, ok=ok)
+        @staticmethod
+        def mutate(root, args, context, info):
+            person = Person(name=args.get('name'))
+            ok = True
+            return CreatePerson(person=person, ok=ok)
 
 **person** and **ok** are the output fields of the Mutation when is
 resolved.