Flora arctica containing descriptions of the flowering plants and ferns, found in the arctic regions, with their distribution in these countries, illustrated by numerous figures in the text, edited by C. H. Ostenfeld, Inspector of the Botanical Museum of the University of Copenhagen. Part I. Pteridophyta, Gymnospermae and Mono co tyledon es, by O. Gelert and C. H. Ostenfeld. Published by the Carlsberg Fund. Copenhagen, Det Nordiske Forlag. 1902.

Hartz, N. (1904). Flora arctica containing descriptions of the flowering plants and ferns, found in the arctic regions, with their distribution in these countries, illustrated by numerous figures in the text, edited by C. H. Ostenfeld, Inspector of the Botanical Museum of the University of Copenhagen. Part I. Pteridophyta, Gymnospermae and Mono co tyledon es, by O. Gelert and C. H. Ostenfeld. Published by the Carlsberg Fund. Copenhagen, Det Nordiske Forlag. 1902. Geografisk Tidsskrift - Danish Journal of Geography, 17. Retrieved from https://tidsskrift.dk/geografisktidsskrift/article/view/49229