Harry F. Druce

Follow

Person

Harpenden, Hertfordshire AL5 3BW, GB

People

Patents Grantslast 30 patents

Information Patent Grant
Playing cards for an educational game
- Patent number 5,836,587
- Issue date Nov 17, 1998
- Harry Frederick Druce
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS
Information Patent Grant
Playing cards for an educational game
- Patent number 5,551,700
- Issue date Sep 3, 1996
- Harry F. Druce
- G09 - EDUCATION CRYPTOGRAPHY DISPLAY ADVERTISING SEALS