Hoyrup, J. (2009). Hesitating progress: The slow development toward algebraic symbolization in abbacus- and related manuscripts, c 1300 to c. 1550. Max-Planck-Institut für Wissenschaftsgeschichte.
Chicago-viite (17. p.)Hoyrup, Jens. Hesitating Progress: The Slow Development Toward Algebraic Symbolization in Abbacus- and Related Manuscripts, C 1300 to C. 1550. Berlin: Max-Planck-Institut für Wissenschaftsgeschichte, 2009.
MLA-viite (8. p.)Hoyrup, Jens. Hesitating Progress: The Slow Development Toward Algebraic Symbolization in Abbacus- and Related Manuscripts, C 1300 to C. 1550. Max-Planck-Institut für Wissenschaftsgeschichte, 2009.
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