Great Britain. Patent Office. (1869). Patents for inventions: Abridgements of specifications relating to writing instruments and materials. Office of the Commissioners of Patents for Inventions.
Citazione stile Chigago Style (17a edizione)Great Britain. Patent Office. Patents for Inventions: Abridgements of Specifications Relating to Writing Instruments and Materials. Lond.: Office of the Commissioners of Patents for Inventions, 1869.
Citatione MLA (8a ed.)Great Britain. Patent Office. Patents for Inventions: Abridgements of Specifications Relating to Writing Instruments and Materials. Office of the Commissioners of Patents for Inventions, 1869.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.