--- a/src/pyams_sequence/widget/__init__.py	Thu Oct 08 12:21:45 2015 +0200
+++ b/src/pyams_sequence/widget/__init__.py	Tue May 16 11:20:42 2017 +0200
@@ -21,8 +21,8 @@
 from pyams_form.interfaces.form import IFormLayer
 from pyams_i18n.interfaces import II18n
 from pyams_sequence.interfaces import ISequentialIntIds, ISequentialIdInfo
-from pyams_sequence.schema import IInternalReference
-from pyams_sequence.widget.interfaces import IInternalReferenceWidget
+from pyams_sequence.schema import IInternalReference, IInternalReferencesList
+from pyams_sequence.widget.interfaces import IInternalReferenceWidget, IInternalReferencesListWidget
 
 try:
     from pyams_workflow.interfaces import IWorkflowVersions, IWorkflowVersion, IWorkflowManagedContent
@@ -31,17 +31,18 @@
 else:
     handle_workflow = True
 
-from z3c.form.interfaces import IFieldWidget
+from z3c.form.interfaces import IFieldWidget, IDataConverter
 
 # import packages
 from hypatia.catalog import CatalogQuery
-from hypatia.query import Eq
+from hypatia.query import Eq, Any
 from pyams_catalog.query import CatalogResultSet
 from pyams_form.widget import widgettemplate_config
 from pyams_sequence.utility import get_last_version
 from pyams_utils.adapter import adapter_config
 from pyams_utils.registry import get_utility
 from z3c.form.browser.widget import HTMLInputWidget
+from z3c.form.converter import BaseDataConverter
 from z3c.form.widget import Widget, FieldWidget
 from zope.interface import implementer_only
 
@@ -58,9 +59,11 @@
 class InternalReferenceWidget(HTMLInputWidget, Widget):
     """Internal reference widget"""
 
+    content_type = None
+
     @property
     def query_params(self):
-        return json.dumps({'content_type': self.field.content_type})
+        return json.dumps({'content_type': self.content_type or self.field.content_type})
 
     @property
     def values_map(self):
@@ -81,3 +84,57 @@
 def InternalReferenceFieldWidget(field, request):
     """Internal reference field widget factory"""
     return FieldWidget(field, InternalReferenceWidget(request))
+
+
+#
+# Internal references list widget
+#
+
+@adapter_config(context=(IInternalReferencesList, IInternalReferencesListWidget), provides=IDataConverter)
+class InternalReferencesListDataConverter(BaseDataConverter):
+    """Internal references list data converter"""
+
+    def toWidgetValue(self, value):
+        if not value:
+            return ''
+        return ','.join(value)
+
+    def toFieldValue(self, value):
+        if not value:
+            return []
+        return value.split(',')
+
+
+@widgettemplate_config(mode='input', template='templates/references-list-input.pt', layer=IFormLayer)
+@widgettemplate_config(mode='display', template='templates/references-list-display.pt', layer=IFormLayer)
+@implementer_only(IInternalReferencesListWidget)
+class InternalReferencesListWidget(HTMLInputWidget, Widget):
+    """Internal references list widget"""
+
+    content_type = None
+
+    @property
+    def query_params(self):
+        return json.dumps({'content_type': self.content_type or self.field.content_type})
+
+    @property
+    def values_map(self):
+        catalog = get_utility(ICatalog)
+        sequence = get_utility(ISequentialIntIds)
+        values = self.value
+        if isinstance(values, str):
+            values = values.split(',')
+        params = Any(catalog['oid'], values)
+        results = {}
+        for item in map(get_last_version, CatalogResultSet(CatalogQuery(catalog).query(params))):
+            oid_info = ISequentialIdInfo(item)
+            results.update({oid_info.hex_oid: '{0} ({1})'.format(II18n(item).query_attribute('title',
+                                                                                             request=self.request),
+                                                                 sequence.get_short_oid(oid_info.oid))})
+        return json.dumps(results)
+
+
+@adapter_config(context=(IInternalReferencesList, IFormLayer), provides=IFieldWidget)
+def InternalReferencesListFieldWidget(field, request):
+    """Internal references list field widget factory"""
+    return FieldWidget(field, InternalReferencesListWidget(request))