Salmonsens konversationsleksikon.
Blangstrup, Johan Christian,1857-1926.
Brøndum-Nielsen, Johannes,1881-
Raunkjaer, Palle,1886-
København : J.H. Schultz,
1915-1930.
Vols. 22-26, "redigeret af Johs. Brøndum-Nielsen og Palle Raunkjær".
Vol. 26: Supplement.
Encyclopedias and dictionaries, Danish.