His first major work was "Triassic fishes from Spitzbergen" (part I: Vienna 1921; part II: Stockholm 1925) was based on material collected during his expeditions to Spitzbergen in 1912, 1913, 1915 and 1916.
Результаты исследований материалов этих экспедиций легли в основу его докторской диссертации «Triassic fishes from Spitzbergen» (первая часть издана в 1921, вторая в 1925).