--- a/src/pyams_content/shared/common/zmi/summary.py	Fri Nov 10 12:07:43 2017 +0100
+++ b/src/pyams_content/shared/common/zmi/summary.py	Tue Nov 14 14:05:30 2017 +0100
@@ -17,7 +17,7 @@
 from datetime import datetime
 
 # import interfaces
-from pyams_content.shared.common.interfaces import IWfSharedContent, IWfSharedContentRoles, ISharedTool
+from pyams_content.shared.common.interfaces import IWfSharedContent, IWfSharedContentRoles, IBaseSharedTool
 from pyams_form.interfaces.form import IWidgetForm, IInnerTabForm, IInnerSubForm
 from pyams_skin.interfaces import IInnerPage
 from pyams_skin.layer import IPyAMSLayer
@@ -37,7 +37,6 @@
 from pyams_viewlet.viewlet import contentprovider_config
 from pyams_zmi.form import AdminDisplayForm, InnerAdminDisplayForm, InnerAdminAddForm
 from z3c.form import field
-from z3c.form.browser.checkbox import SingleCheckBoxFieldWidget
 from zope.interface import implementer, Interface
 
 from pyams_content import _
@@ -61,7 +60,7 @@
 
     @property
     def back_url(self):
-        tool = get_parent(self.context, ISharedTool)
+        tool = get_parent(self.context, IBaseSharedTool)
         return absolute_url(tool, self.request, 'admin')