Naumov 2006, pp. 53, After Novgorod had been annexed by the newly emerging centralized Russian state in 1478, its government, located in Moscow, tried to lay claim to Yugor Land as well... In 1483 Prince Ivan III sent a large expeditionary force to Siberia... In 1499–1500 Ivan III sent another large force. Naumov, Igor V. (22 November 2006). The History of Siberia. Routledge. ISBN978-1-134-20703-9.
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