1 | Contaminants entering the sea : data appendix : data on contaminant loads entering the seas around England and Wales for the years 1990-1993 |
2 | The quality of rivers, canals and estuaries in England and Wales : report of the 1990 survey |
3 | River quality in England and Wales : a report of the 1990 survey |
4 | The 1990 river and estuary classification survey of England and Wales |
5 | Biological characteristics and exploitation of sea trout in the River Tywi during 1989 |