Who wrote the novel "Through the Montana Mountains"?

Wiesław Wernic (1906-1986), popular Polish writer and journalist, best known for his series of Wild West books, sometimes called "Polish Karl May". During World War II fought in the Warsaw Uprising, after the war worked for a Polish daily Rzeczpospolita and weekly "Tygodnik Demokratyczny". Unlike Karl May to whom he was often compared, Wernic visited United States a number of times where he met with American Indians and was a leading authority on the history and customs of the Wild West.