V. Walfrid Ekman: On Dead-water. With a preface by Professor Vilhelm Bjerknes. The Norwegian North Polar Expedition 1893—1896. Scientific Results Vol. V No. XV.

Gehrke, J. (1908). V. Walfrid Ekman: On Dead-water. With a preface by Professor Vilhelm Bjerknes. The Norwegian North Polar Expedition 1893—1896. Scientific Results Vol. V No. XV. Geografisk Tidsskrift, 19. Hentet fra https://tidsskrift.dk/geografisktidsskrift/article/view/49398