https://crossref.org/documentation/register-maintain-records/verify-your-registration/notification-callback-service/
Notification callback service - Crossref
Notification callback is a service you can use to notify you when a submission log, either in the test or production admin tool, is available for a metadata,...
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https://uwtcallbackservice.com/
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https://www.ibm.com/docs/en/wm-integration-ipaas?topic=cecssfs-configuring-error-callback-service-spec-flow-service-by-using-example
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Know how to configure the Error Callback Service Spec flow service by using an example.
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https://instantcallback.in/
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