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We use these keys to gather relevant statistics about the usage of the API so that we can better improve it and be able to provide a better customer support. If abuse of these key is detected, Europeana Foundation may enforce limits to its usage or even block access to the Europeana APIs.
For this reason, we strongly recommend to not share these keys with third parties or expose it in user interfaces, code or in markup as the API keys are confidential and are for use by the client application or invidual only.
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