Wendy Wax. (2007). Piggley Makes a Friend (Ready-to-Read. Level 1). Simon Spotlight.
Chicago-viite (17. p.)Wendy Wax. Piggley Makes a Friend (Ready-to-Read. Level 1). Simon Spotlight, 2007.
MLA-viite (9. p.)Wendy Wax. Piggley Makes a Friend (Ready-to-Read. Level 1). Simon Spotlight, 2007.
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