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Natsuko Toyoda, The Key to Success (PDF), in Japan Spotlight, vol. 169, Tokyo, Japan Economic Foundation, gennaio–febbraio 2010, ISSN 1348-9216 (WC · ACNP).
Natsuko Toyoda, The Key to Success (PDF), in Japan Spotlight, vol. 169, Tokyo, Japan Economic Foundation, gennaio–febbraio 2010, ISSN 1348-9216 (WC · ACNP).