APA (7th ed.) Citation

Hugo Helbing (Firma) & Hugo Helbing (Firma). (1930). Sammlung A. Adelsberger, Nürnberg. Hugo Helbing.

Chicago Style (17th ed.) Citation

Hugo Helbing (Firma) and Hugo Helbing (Firma). Sammlung A. Adelsberger, Nürnberg. München: Hugo Helbing, 1930.

MLA (9th ed.) Citation

Hugo Helbing (Firma) and Hugo Helbing (Firma). Sammlung A. Adelsberger, Nürnberg. Hugo Helbing, 1930.

Warning: These citations may not always be 100% accurate.