Act of August 7, 1961, Public Law 87-126, 75 STAT 284, which established the Cape Cod National Seashore.

Chicago citation style
National Archives and Records Administration. Office of the Federal Register. 4/1/1985-. Act of August 7, 1961, Public Law 87-126, 75 STAT 284, which established the Cape Cod National Seashore.. 1961-08-07. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/299873. (Accessed June 23, 2018.)
APA citation style
National Archives and Records Administration. Office of the Federal Register. 4/1/1985-, (1961-08-07) Act of August 7, 1961, Public Law 87-126, 75 STAT 284, which established the Cape Cod National Seashore.. Retrieved from the Digital Public Library of America, http://catalog.archives.gov/id/299873
MLA citation style
National Archives and Records Administration. Office of the Federal Register. 4/1/1985-. Retrieved from the Digital Public Library of America <http://catalog.archives.gov/id/299873>.
Note: These citations are programmatically generated and may be incomplete.