The National Park Service and the State Historic Preservation Office publish materials on a wide range of preservation topics. On this page you can access the National Park Service's National Register Bulletins series which provides detailed guidance about how to apply the National Register criteria (for example, how to assess the eligibility of less than fifty year old properties, how to assess significance of properties associated with important persons, etc.) and the Preservation Briefs, supplemental guidance for applying the Secretary of the Interior's Standards and Guidelines for Rehabilitation (particularly useful to persons carrying out rehabilitation projects for federal and state tax credits).
The SHPO publishes a series of Fact Sheets designed to provide quick references on its various programs, including the National Register, Section 106, Certified Local Governments, Tax Credits, and much more. Oklahoma's National Register Handbook, which includes information about the nomination process, criteria, and a listing of Oklahoma properties in the register, is another SHPO publication found on this page.