"Ryssland. Gränser." . . "Russia, Historical geography." . . "Russie - Géographie historique." . . "Turner, Hypothèse de." . . "URSS Géographie historique." . . "Russie" . . "Soviet Union" . . "Soviet Union." . "Frontier and pioneer life, Russia." . . "frontière Russie URSS origines 1922." . . "Frontier and pioneer life Soviet Union." . . "Russie - Histoire." . . "Frontier thesis." . . "The Russian frontier : the impact of Borderlands upon the course of early Russian history" . . . . . . . . . . . . . . . . . . . . . . "History" . "History"@en . . . . "The Russian frontier : the impact of borderlands upon the course of early Russian history" . "The Russian frontier : the impact of borderlands upon the course of early Russian history"@en . . . . . . . . . . . . . . . "The Russian frontier : The impact of borderlands upon the course of early Russian history" . . "The Russian frontier the impact of borderlands upon the course of early Russian history"@en . "Russland." . . "Historical geography." . . "Grenze." . . "Vie des pionniers." . . "Geschichte." . . "Russia, History." . . "Russia" . . "Russia." . . . "Frontier and pioneer life." . .