CBAC TGAU Daearyddiaeth: Llyfr Gwaith (WJEC GCSE Geography Workbook Welsh-language edition) Owen Andy Heftet / 2019 / Walisisk
GCSE Geography Fieldwork Handbook for WJEC (Wales) Geographical skills Owen Andy Heftet / 2018 / Engelsk
CBAC TGAU Daearyddiaeth Ail Argraffiad (WJEC GCSE Geography Second Edition Welsh-language edition) Owen Andy Heftet / 2024 / Walisisk