Tupikova, I., & Soffel, M. Modelling ancient sundials: Ancient and modern errors / Irina Tupikova. Michael Soffel. Productive errors : scientific concepts in Antiquity.(2012).
Chicago-viite (17. p.)Tupikova, Irina, ja Michael Soffel. "Modelling Ancient Sundials: Ancient and Modern Errors / Irina Tupikova. Michael Soffel." Productive Errors : Scientific Concepts in Antiquity.(2012) .
MLA-viite (8. p.)Tupikova, Irina, ja Michael Soffel. "Modelling Ancient Sundials: Ancient and Modern Errors / Irina Tupikova. Michael Soffel." Productive Errors : Scientific Concepts in Antiquity.(2012), .
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