QuoteCancel/FIX.4.2

Message Content of QuoteCancel (MsgType=Z)

TagText	FieldName or ComponentName	Required	Description
	StandardHeader	x	MsgType = Z
131	QuoteReqID		Required when quote is in response to a Quote Request message
117	QuoteID	x
298	QuoteCancelType	x	Identifies the type of Quote Cancel request.
301	QuoteResponseLevel		Level of Response requested from receiver of quote messages.
336	TradingSessionID
295	NoQuoteEntries	x	The number of securities whose quotes are to be canceled
55	Symbol	x	Must be the first field in the repeating group.
65	SymbolSfx		Can be repeated multiple times if message is related to multiple symbols.
48	SecurityID		Can be repeated multiple times if message is related to multiple symbols.
22	IDSource		Can be repeated multiple times if message is related to multiple symbols.
167	SecurityType		Must be specified if a Future or Option. If a Future:Symbol, SecurityType, and MaturityMonthYear are required. If an Option:Symbol, SecurityType, MaturityMonthYear, PutOrCall, and StrikePrice are required.
200	MaturityMonthYear		Specifiesthe month and year of maturity. Required if MaturityDay is specified.
205	MaturityDay		Can be used in conjunction with MaturityMonthYear to specify a particular maturity date.
201	PutOrCall		For Options.
202	StrikePrice		For Options.
206	OptAttribute		For Options.
231	ContractMultiplier		For Fixed Income, Convertible Bonds, Derivatives, etc. Note: If used, quantities should be expressed in the "nominal" (e.g. contracts vs. shares) amount.
223	CouponRate		For Fixed Income.
207	SecurityExchange		Can be used to identify the security.
106	Issuer		Can be repeated multiple times if message is related to multiple symbols.
348	EncodedIssuerLen		Must be set if EncodedIssuer field is specified and must immediately precede it.
349	EncodedIssuer		Encoded (non-ASCII characters) representation of the Issuer field in the encoded format specified via the MessageEncoding field.
107	SecurityDesc		Can be repeated multiple times if message is related to multiple symbols.
350	EncodedSecurityDescLen		Must be set if EncodedSecurityDesc field is specified and must immediately precede it.
351	EncodedSecurityDesc		Encoded (non-ASCII characters) representation of the SecurityDesc field in the encoded format specified via the MessageEncoding field.
311	UnderlyingSymbol		The symbol of the underlying security of options that should be canceled.
	StandardTrailer	x

Notes

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Don't forget to refer to the FPL Discussion Groups to back up anything you write.
You will often find the authoritative statements on matters of FIX specification interpretation there.
Links from FIXwiki pages to relevant discussions on the FPL site are very valuable.

For example if you were writing a clarification on how to specify the "quantity" of an order in FIX, you might add the
following relevant link, http://www.fixprotocol.org/discuss/read/f5014573, to back up your points.