@en|Scanning of a 1955 [[Sheaffer]] advertising for a pen/pencil set of the [[Snorkel Pen]], ''Crest'' version. Published on ''The National Geographic Magazine''. Retouched by the author for a better sharpness. Date from copyright note. | @en|Scanning of a 1955 [[Sheaffer]] advertising for a pen/pencil set of the [[Snorkel Pen]], ''Crest'' version. Published on ''The National Geographic Magazine''. Retouched by the author for a better sharpness. Date from copyright note. |