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If you have any questions, you are always welcome to contact us. We'll get back to you as soon as possible, withing 24 hours on weekdays.
Customer service
All questions about your order, return and delivery must be sent to our customer service team by e-mail at yourstore@yourdomain.com
Sale & Press
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This survey highlights the leading features in the development of the wasan, the Japanese system of mathematics. Topics include the use of the abacus; the application of sangi, or counting rods, to algebra; the yenri, or circle principle; the work of Seki Kowa, Ajima Chokuyen and Wada Nei; more. 1914 edition. Includes 74 figures.
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