Most UK ISPs use the IWF's list of proscribed sites as a guide on filtering out images showing child abuse and other illegal content.
Wikipedia volunteers say The Scorpions' album cover image of a girl has never been banned.
They are also unhappy that the text entry for The Scorpions is also being blocked, reports the BBC.
The Wikipedia database contains over two million articles in English, written and edited by volunteers and users of the multi-lingual site.
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