{"links": [{"url": "http://www.envisionthepast.com/library-us-history-3/", "type": {"key": "/type/link"}, "title": "U.S. History; Constitutional Period to 1845"}], "title": "Westward extension", "created": {"type": "/type/datetime", "value": "2009-12-11T06:43:03.322575"}, "last_modified": {"type": "/type/datetime", "value": "2016-08-03T18:25:07.175870"}, "latest_revision": 3, "key": "/works/OL12355698W", "authors": [{"type": {"key": "/type/author_role"}, "author": {"key": "/authors/OL2029622A"}}], "type": {"key": "/type/work"}, "revision": 3}