Amstein, T. (2015). Benchmarking of outdoor activity facilities: An analysis of German hiking facilities and its implications to Finland.
Chicago-viite (17. p.)Amstein, Torsten. Benchmarking of Outdoor Activity Facilities: An Analysis of German Hiking Facilities and Its Implications to Finland. Jyväskylä, 2015.
MLA-viite (9. p.)Amstein, Torsten. Benchmarking of Outdoor Activity Facilities: An Analysis of German Hiking Facilities and Its Implications to Finland. 2015.
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