1 January 1988 - 1 January 1991
| DOI | https://doi.org/10.48597/7FJ6-BSJD |
|---|---|
| Start time | 1 January 1988 |
| Stop time | 1 January 1991 |
| DOI | https://doi.org/10.48597/V2EA-WQZW |
|---|---|
| Start time | 1 January 1988 |
| Stop time | 1 January 1990 |
| DOI | https://doi.org/10.48597/9B7Y-W5U3 |
|---|---|
| Start time | 1 January 1988 |
| Stop time | 1 January 1989 |