The NPS Electronic Library is a portal to thousands of electronic publications, covering the cultural and natural history of the National Park Service and the national parks, monuments, and historic sites of the U.S. National Park System. Included are a variety of NPS newsletters (e.g., Common Ground, Heritage Matters, Preservation Tech Notes), publications (e.g., BAE Bulletins, Reports of the Chaco Center, Urban Ecology), and more.
NPShistory.com was created by two individuals who have a passion for the National Park System: Dr. Harry A. Butowsky and Randall D. Payne. Both have extensive experience working and volunteering, respectively, with the NPS.
For National Park Service resources from the official website, go to: http://www.nps.gov/history/publications.htm