| Country | Statutory Instrument |
|---|---|
| Philippines | 1989 No. 2002 |
| Portugal | 1979 No. 921 1987 No. 1831 (Protocol) |
| Spain | 1975 No. 415 1976 No. 1916 (Protocol) |
| Sweden | 1988 No. 590 1992 No. 3213 (Protocol) |
| Switzerland | 1969 No. 384 |
| Turkey | 1961 No. 584 |
| United States of America | 1984 No. 1817 1997 No. 1778 (Protocol) |
| Yugoslavia | 1958 No. 1263 |
