Geologisk Kart over Christiania Omegn af Theodor Kjerulf 1864.
MLA
Geologisk Kart over Christiania Omegn Af Theodor Kjerulf 1864. 1864. https://collections.library.yale.edu/catalog/15471537.
APA, 6th edition
Geologisk Kart over Christiania Omegn af Theodor Kjerulf 1864. (1864). [Maps]. https://collections.library.yale.edu/catalog/15471537.