[CT-Guidelines Last Call] Clarification needed

4.2.3.1

If a server varies its representation according to examination of received HTTP headers then it must include a Vary HTTP header indicating this to be the case. If, in addition to, or instead of HTTP headers, a server varies its representation based on other factors (e.g. source IP Address) then it must, in accordance with [RFC 2616 HTTP]<http://www.w3.org/TR/2008/WD-ct-guidelines-20080801/#ref-HTTP>, include a Vary header containing the value '*'.

What should contain the Vary HTTP Header when a server varies its representation according to examination of received HTTP headers?

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