diff --git a/mongoengine/dereference.py b/mongoengine/dereference.py
index 18b365ccd..c4b792559 100644
--- a/mongoengine/dereference.py
+++ b/mongoengine/dereference.py
@@ -104,7 +104,10 @@ def _find_references(self, items, depth=0):
                         # LazyReference inherits DBRef but should not be dereferenced here !
                         continue
                     elif isinstance(v, DBRef):
-                        reference_map.setdefault(field.document_type, set()).add(v.id)
+                        if hasattr(v, 'cls'):
+                            reference_map.setdefault(get_document(v.cls), set()).add(v.id)
+                        else:
+                            reference_map.setdefault(field.document_type, set()).add(v.id)
                     elif isinstance(v, (dict, SON)) and '_ref' in v:
                         reference_map.setdefault(get_document(v['_cls']), set()).add(v['_ref'].id)
                     elif isinstance(v, (dict, list, tuple)) and depth <= self.max_depth:
@@ -112,13 +115,17 @@ def _find_references(self, items, depth=0):
                         references = self._find_references(v, depth)
                         for key, refs in references.iteritems():
                             if isinstance(field_cls, (Document, TopLevelDocumentMetaclass)):
-                                key = field_cls
+                                if not field_cls._meta.get('abstract', False):
+                                    key = field_cls
                             reference_map.setdefault(key, set()).update(refs)
             elif isinstance(item, LazyReference):
                 # LazyReference inherits DBRef but should not be dereferenced here !
                 continue
             elif isinstance(item, DBRef):
-                reference_map.setdefault(item.collection, set()).add(item.id)
+                if hasattr(item, 'cls'):
+                    reference_map.setdefault(get_document(item.cls), set()).add(item.id)
+                else:
+                    reference_map.setdefault(item.collection, set()).add(item.id)
             elif isinstance(item, (dict, SON)) and '_ref' in item:
                 reference_map.setdefault(get_document(item['_cls']), set()).add(item['_ref'].id)
             elif isinstance(item, (dict, list, tuple)) and depth - 1 <= self.max_depth:
diff --git a/mongoengine/fields.py b/mongoengine/fields.py
index a661874a5..6e652ec16 100644
--- a/mongoengine/fields.py
+++ b/mongoengine/fields.py
@@ -2257,7 +2257,11 @@ def build_lazyref(self, value):
             if isinstance(value, self.document_type):
                 value = LazyReference(self.document_type, value.pk, passthrough=self.passthrough)
             elif isinstance(value, DBRef):
-                value = LazyReference(self.document_type, value.id, passthrough=self.passthrough)
+                # Honor cls field on DBRef for Abstract Documents
+                if hasattr(value, 'cls'):
+                    value = LazyReference(get_document(value.cls), value.id, passthrough=self.passthrough)
+                else:
+                    LazyReference(self.document_type, value.id, passthrough=self.passthrough)
             else:
                 # value is the primary key of the referenced document
                 value = LazyReference(self.document_type, value, passthrough=self.passthrough)
@@ -2302,7 +2306,10 @@ def validate(self, value):
             pk = value.pk
         elif isinstance(value, DBRef):
             # TODO: check collection ?
-            collection = self.document_type._get_collection_name()
+            if hasattr(value, 'cls'):
+                collection = get_document(value.cls)._get_collection_name()
+            else:
+                collection = self.document_type._get_collection_name()
             if value.collection != collection:
                 self.error("DBRef on bad collection (must be on `%s`)" % collection)
             pk = value.id