| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| CZECHOSLOVAKIA | Signature | 30/10/1928 | |
| DENMARK | Signature | 30/10/1928 | |
| FRANCE | Signature | 30/10/1928 | |
| GERMANY | Signature | 30/10/1928 | |
| POLAND | Signature | 30/10/1928 | |
| SWEDEN | Signature | 30/10/1928 | |
| UNITED KINGDOM | Signature | 30/10/1928 |