Analysis of information sources in references of the Wikipedia article "European Classification" in English language version.
The European Classification (ECLA) system used by the European Patent Office represents a downward expansion of the IPC system by including over 70,000 subclasses. (quote from page 1795)
The European Classification (ECLA) system used by the European Patent Office represents a downward expansion of the IPC system by including over 70,000 subclasses. (quote from page 1795)