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Secret is secret Key used to protect API Key (Instance key) if third-party programmers were involved for development or someone from the company quit, etc. Usually not required. We can generate one for you in future and Signature and timestamp will be automatically generated. Here is more information if you need to use Secret key http://docs.otapi.net/en/Documentations/Description/MethodSignature 

XML and JSON

To get response in XML format send request to http://otapi.net/service/

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