| Act(s) | Article(s) | Signature | Instrument | Entry into Force |
|---|---|---|---|---|
| Stockholm Act (1967) | July 14, 1967 | Ratification : February 21, 1972 | May 25, 1972 | |
| Lisbon Act (1958) | October 31, 1958 | |||
| London Act (1934) | June 2, 1934 | Accession : December 8, 1950 | January 28, 1951 | |
| The Hague Act (1925) | Accession : May 8, 1933 | July 14, 1933 |