| Act(s) | Article(s) | Signature | Instrument | Entry into Force |
|---|---|---|---|---|
| Additional Act of Stockholm (1967) | July 14, 1967 | Ratification : June 27, 1975 | October 4, 1975 | |
| Lisbon Act (1958) | October 31, 1958 | Ratification : September 2, 1961 | June 1, 1963 | |
| London Act (1934) | Accession : February 9, 1956 | April 29, 1956 |