[1] Bitfinex API Reference (5/11/2016, 10:24:33 PM) <http://docs.bitfinex.com/#authentication>
These are encoded as HTTP headers named:X-BFX-APIKEYX-BFX-PAYLOADX-BFX-SIGNATURE
These are encoded as HTTP headers named:
X-BFX-APIKEY
X-BFX-PAYLOAD
X-BFX-SIGNATURE
Google search: X-BFX-SIGNATURE: