'In 1954 Hildaur Nielsen invented this filing system using slotted cards on a cylinder'
Rolodex
INVENTORS & INVENTIONS: In 1954 Hildaur Nielsen invented this filing system using slotted cards on a cylinder
In 1954 Hildaur Nielsen invented this filing system using slotted cards on a cylinder
In 1954 Hildaur Nielsen invented this filing system using slotted cards on a cylinder
INVENTORS & INVENTIONS
Rolodex
INVENTORS & INVENTIONS