Adding missing reference to min_length in rules reference
diff --git a/user_guide_src/source/libraries/form_validation.rst b/user_guide_src/source/libraries/form_validation.rst
index 032cff2..8534175 100644
--- a/user_guide_src/source/libraries/form_validation.rst
+++ b/user_guide_src/source/libraries/form_validation.rst
@@ -866,6 +866,7 @@
**is_unique** Yes Returns FALSE if the form element is not unique to the table and field name in the is_unique[table.field]
parameter. Note: This rule requires :doc:`Query Builder <../database/query_builder>` to be
enabled in order to work.
+**min_length** Yes Returns FALSE if the form element is shorter then the parameter value. min_length[3]
**max_length** Yes Returns FALSE if the form element is longer then the parameter value. max_length[12]
**exact_length** Yes Returns FALSE if the form element is not exactly the parameter value. exact_length[8]
**greater_than** Yes Returns FALSE if the form element is less than or equal to the parameter value or not greater_than[8]