APA

U.S. Dept. of the Interior, .It's your world: the grassroots conservation story. Washington, For sale by the Supt. of Docs: U.S. Govt. Print. Off.,1c1969.

Chicago

U.S. Dept. of the Interior, .It's your world: the grassroots conservation story. Washington, For sale by the Supt. of Docs: U.S. Govt. Print. Off.,1c1969.

Harvard

U.S. Dept. of the Interior, .It's your world: the grassroots conservation story. Washington, For sale by the Supt. of Docs: U.S. Govt. Print. Off.,1c1969.

MLA

U.S. Dept. of the Interior, .Washington, For sale by the Supt. of Docs: U.S. Govt. Print. Off.,1c1969. .