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Google Analytics use of cookies: https://developers.google.com/ analytics/devguides/collection/ analyticsjs/cookie-usage?hl=en-GB

How Google uses cookies: www.google.co.uk/ intl/en-GB/policies/ technologies/cookies

How Facebook uses cookies: www.facebook.com/ policies/cookies/

An article on the BBC website explaining cookies: www.bbc.co.uk/webwise/guides/about-cookies

The Information Commissioners Office information on cookies: ico.org.uk/for-the-public/online/cookies

How to change your browser settings for cookies: www.aboutcookies.org.uk/ managing-cookies