The evolution of agricultural nature management models in the Baltic States and the Kaliningrad region in 1890—2016
... I. Jahrgang. B., 1863. URL:
https://books.google.ru/books/about/Jahrbuch_für_die_Amtliche_Statistik_des.html?hl=tr&id=Ko...
(дата обращения: 18.06.2016).
Vinogradova O. V.
regional models of agricultural nature management, stages of agricultural evolution, historical and geographical method
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