def get_mentions(self, docs=None, sort=False):
        result = []
        if docs:
            docs = docs if isinstance(docs, (list, tuple)) else [docs]
            for mention_class in self.mention_classes:
                mentions = (
                    self.session.query(mention_class)
                    .filter(mention_class.document_id.in_([doc.id for doc in docs]))
                    .order_by(mention_class.id)
                    .all()
                )
                if sort:
                    mentions = sorted(mentions, key=lambda x: x[0].get_stable_id())
                result.append(mentions)
        else:
            for mention_class in self.mention_classes:
                mentions = (
                    self.session.query(mention_class).order_by(mention_class.id).all()
                )
                if sort:
                    mentions = sorted(mentions, key=lambda x: x[0].get_stable_id())
                result.append(mentions)
        return result