APA

United States, . (1966). Sweden's Social Security System. [Washington, D.C: .

Chicago

United States, . 1966. Sweden's Social Security System. [Washington, D.C: .

Harvard

United States, . (1966). Sweden's Social Security System. [Washington, D.C: .

MLA

United States, . Sweden's Social Security System. [Washington, D.C: . 1966.