22bcaf1d_ers___Superfeedr_Documentation__Value
[Parameter Name] format [Note] optional [Value] 
json if you want to receive notifications as json format (for feeds only!). You can also use an Accept HTTP header like this: Accept: application/json. atom if you explicitly want to receive notification as Atom. This is used by default for any resource that's either Atom or RSS. If you don't specify any, we will send you the data pulled from the HTTP resource, (excluding feeds).
Subscribers - Superfeedr Documentation
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