Membership
Tour
Register
Log in
Michel Groothuis
Follow
Person
Saint-Imier, CH
People
Overview
Industries
Organizations
People
Information
Impact
Patents Grants
last 30 patents
Information
Patent Grant
Timepiece with a perpetual calendar mechanism
Patent number
4,427,300
Issue date
Jan 24, 1984
Compagnie des Montres Longines
Michel Groothuis
G04 - HOROLOGY