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Nikolai Ivanovich Lobachevsky - The Linda Hall
Nikolai Ivanovich Lobachevsky, a Russian mathematician, was born Dec. 1, 1792. In 1829 and 1830, Lobachevsky published a series of five papers, which
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"Nikolai Lobachevsky" बनाएँ - विकिपीडिया
nikolai lobachevsky