1 | A litter assessment of two major tributaries of the Taff, the Cynon and the Rhondda : surveyed March - April 1990 |
2 | A Status Report on the Direct Oxygenation of the Tywi Estuary - October 1989 |
3 | The River Tywi catchment management plan : action plan (bilingual) |
4 | Biological characteristics and exploitation of sea trout in the River Tywi during 1989 |