Schema.org is a collaborative, community activity with a mission to create, maintain, and promote schemas for structured data on the Internet, on web pages, in email messages, and beyond.
This paper proposes improved ways of indicating open and restricted access, as well as license information, for remote online resources through coordinated changes to the MARC 21 fields 506 (Restrictions on Access Note), 540 (Terms Governing Use and Reproduction Note), and 856 (Electronic Location and Access). (Network Development and MARC Standards Office, Library of Congress)
OpenRefine (formerly Google Refine) is a powerful tool for working with messy data: cleaning it; transforming it from one format into another; and extending it with web services and external data.
P. Missier, K. Belhajjame, and J. Cheney. Proceedings of the 16th International Conference on Extending Database Technology, page 773--776. New York, NY, USA, ACM, (2013)