Gwyddoniaeth trwy brofiad.
Smyth, Steve.
Jones, Elfrys.
Llandysul : Gomer mewn cydweithrediad a Heinemann Educational Books,
1992.
Arg Saesneg gwreiddiol = Original English ed: [London]: Heinemann Educational, 1989
Cyfieithiad Cymraeg gan = Welsh translation by: Elfrys Jones
Teitl clawr = Cover title
Science
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