Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Publication of BE387826ApublicationCriticalpatent/BE387826A/xx
G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
G09B29/00—Maps; Plans; Charts; Diagrams, e.g. route diagram
G09B29/06—Maps; Plans; Charts; Diagrams, e.g. route diagram of belt form, e.g. endless belt
