Advanced level statistics.
Jones, Gwyn,1940-
Great Britain.Welsh Office.Education Department.
University College of Wales (Aberystwyth, Wales)
Gwynedd (Wales).Education Authority.
Aberystwyth : Y Ganolfan Adnoddau Addysg,
1989.
Research project funded by the Welsh Office Education Department. Prepared by Gwynedd Education Authority and published by Y Ganolfan Adnoddau, University College of Wales.
Statistics