Hollandsche zaadhandel.
MLA
Zwaan, C. Hollandsche Zaadhandel. Mechelen: Hollandsche zaadhandel NV, 1934.
APA
Zwaan, C. (1934). Hollandsche zaadhandel. Mechelen: Hollandsche zaadhandel NV.
Chicago
Zwaan, C. Hollandsche Zaadhandel. Mechelen: Hollandsche zaadhandel NV, 1934.