John Jackman; Wendy Wren. (2013). Writing: Teacher's Guide 4 (Collins Primary Focus) (New edition.). HarperCollins UK.
Chicago-viite (17. p.)John Jackman; Wendy Wren. Writing: Teacher's Guide 4 (Collins Primary Focus). New edition. HarperCollins UK, 2013.
MLA-viite (9. p.)John Jackman; Wendy Wren. Writing: Teacher's Guide 4 (Collins Primary Focus). New edition. HarperCollins UK, 2013.
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