Antigua and Barbuda (effective November 1981)
Argentina (effective July 1968)
Austria (except from January 1958 through June 1961)
Bahamas, Commonwealth of the (effective October 1974)
Barbados (effective July 1968)
Belgium (effective July 1968)
Belize (effective September 1981)
Bolivia
Brazil
Burkina Faso, Republic of (formerly Upper Volta)
Canada (effective January 1966)
Chile
Colombia (effective January 1967)
Costa Rica (effective May 1962)
Cyprus (effective October 1964)
Czechoslovakia (effective July 1968)
Denmark (effective April 1964)
Dominica (effective November 1978)
Dominican Republic (effective November 1984)
Ecuador
El Salvador (effective January 1969)
Finland (effective May 1968)
France (effective June 1968)
Gabon (effective June 1964)
Grenada (effective April 1983)
Guatemala (effective October 1978)
Guyana (effective September 1969)
Iceland (effective December 1980)
Ivory Coast
Jamaica (effective July 1968)
Liechtenstein (effective July 1968)
Luxembourg
Malta (effective September 1964)
Mexico (effective March 1968)
Monaco
Netherlands (effective July 1968)
Nicaragua (effective May 1986)
Norway (effective June 1968)
Panama
Peru (effective February 1969)
Philippines (effective June 1960)
Poland (effective March 1957)
Portugal (effective May 1968)
San Marino (effective January 1965)
Spain (effective May 1966)
St. Christopher and Nevis (effective September 1983)
St. Lucia (effective August 1984)
Sweden (effective July 1966)
Switzerland (effective July 1968)
Trinidad and Tobago (effective July 1975)
Trust Territory of the Pacific Islands (Micronesia) (effective July 1976)
Turkey
United Kingdom
Western Samoa (effective August 1972)
Yugoslavia
Zaire (effective July 1961) (formerly Congo (Kinshasa))
20 C.F.R. §404.463