https://www.boc.cn/mo/en/fimarkets/fm4/201902/t20190214_14817630.html
Foreign Exchange Option and Options Combination
foreign exchange optionoptionscombination
https://www.cmegroup.com/notices/clearing/2016/04/Chadv16-162.html
Product Modification Summary: Adding Third Serial Month to Certain CME Foreign Exchange (FX) Option...
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