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Ben Zumdahl

Really helpful tutorial! Thanks a lot! 
but I got only one question, 
I made this request:

And I got this response:

{"code":"rest_invalid_param","message":"Invalid parameter(s): orderby","data":{"status":400,"params":{"orderby":"orderby is not one of author, date, id, include, modified, parent, relevance, slug, title."}}}

Can you please help me where my mistake is ?