diff --git a/doc/en/user/source/filter/ecql_reference.rst b/doc/en/user/source/filter/ecql_reference.rst
index df7944ed642..4c988487912 100644
--- a/doc/en/user/source/filter/ecql_reference.rst
+++ b/doc/en/user/source/filter/ecql_reference.rst
@@ -195,7 +195,7 @@ An attribute name denotes the value of a feature attribute.
 
 * Simple attribute names are sequences of letters and numbers, e.g. `States123`
 * Attribute names quoted with double-quotes may be any sequence of characters, e.g. `"States!@#"`
-* `Note <https://gis.stackexchange.com/a/475826/68995>`_: `id` is a reserved word in the GML spec (for the FeatureID) and thus an attribute (or database column) named `id` must be quoted, e.g. `"id"`
+* `Note <https://gis.stackexchange.com/a/475826/68995>`_: `id` is one of a few `reserved keywords <https://github.com/geotools/geotools/blob/main/modules/library/cql/src/main/jjtree/ECQLGrammar.jjt#L180>`_ in ECQL and thus an attribute (or database column) named `id` must be quoted, e.g. `"id"`
 
 .. _ecql_literal: