fix referenced documents names

Author: xabbuh

book/security.rst

@@ -1437,7 +1437,7 @@ is available by calling the PHP function :phpfunction:`hash_algos`.
 .. tip::
 
     It's also possible to use different hashing algorithms on a user-by-user
-    basis. See :doc:`/cookbook/security/named-encoders` for more details.
+    basis. See :doc:`/cookbook/security/named_encoders` for more details.
 
 Determining the Hashed Password
 ...............................

reference/forms/types/collection.rst

@@ -379,4 +379,4 @@ error_bubbling
 
 .. include:: /reference/forms/types/options/mapped.rst.inc
 
-.. include:: /reference/forms/type/options/cascade_validation.rst.inc
+.. include:: /reference/forms/types/options/cascade_validation.rst.inc

reference/forms/types/options/checkbox_empty_data.rst.inc

@@ -6,4 +6,4 @@ empty_data
 This option determines what value the field will return when the ``empty_value``
 choice is selected.
 In checkbox, the value of ``empty_data`` is overriden by the value returned by
-the data transformer (see :doc:`/cookbook/form/data_transformers.rst`).
+the data transformer (see :doc:`/cookbook/form/data_transformers`).