Document (#20647)

Author
Dickens, D.T.
Title
¬The ECLA classification system
Source
World patent information. 16(1994) no.1, S.28-32
Year
1994
Abstract
The European Classification system is the classification scheme used by the European Patent Office to classify their internal search files and is based on the hierarchical structure of the International Patent Classification (IPC). The ECLA codes are also available and searchable on several commercial online patent databases, particularly the databases on Questel. While ECLA codes are based on the IPC system, they are more specific, overcome many of the IPC's weaknesses and can be used to increase recall in subject searches
Field
Patentinformation
Object
ECLA

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