--- a/src/pyams_content/shared/resource/zmi/widget.py	Wed Nov 06 16:54:59 2019 +0100
+++ b/src/pyams_content/shared/resource/zmi/widget.py	Tue Nov 19 16:39:10 2019 +0100
@@ -47,7 +47,7 @@
 
     def updateWidgets(self, setErrors=True):
         super(AgeRangeWidget, self).updateWidgets(setErrors)
-        widgets = self.subform.widgets
+        widgets = self.widgets
         for name in ('min_value', 'max_value'):
             widget = widgets[name]
             widget.label_css_class = 'control-label col-md-2'