Joyce Vallar. (2011). Spelling: Teacher's Guide 2 (Collins Primary Focus) (New edition.). HarperCollins UK.
Chicago-viite (17. p.)Joyce Vallar. Spelling: Teacher's Guide 2 (Collins Primary Focus). New edition. HarperCollins UK, 2011.
MLA-viite (9. p.)Joyce Vallar. Spelling: Teacher's Guide 2 (Collins Primary Focus). New edition. HarperCollins UK, 2011.
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