Harley, B. (1990). Constructional Toys. Shire Publications Ltd..
Chicago-Zitierstil (17. Ausg.)Harley, Basil. Constructional Toys. Buckinghamshire: Shire Publications Ltd., 1990.
MLA-Zitierstil (8. Ausg.)Harley, Basil. Constructional Toys. Shire Publications Ltd., 1990.
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