[1] Apple News API Reference: Authentication, Authorization, and Confidentiality ( (2016-06-29 11:23:33 +09:00 版)) https://developer.apple.com/library/ios/documentation/General/Conceptual/News_API_Ref/Security.html#//apple_ref/doc/uid/TP40015409-CH5-SW1

Set the Authorization header as:
Authorization: HHMAC; key=<api-key-id>; signature=<hash>; date=<date> where <date> is the date string from step 1.

[2] Apple News API Reference: Read Channel ( (2016-06-29 11:26:51 +09:00 版)) https://developer.apple.com/library/ios/documentation/General/Conceptual/News_API_Ref/ReadChannel.html#//apple_ref/doc/uid/TP40015409-CH9-SW1

Authorization: HHMAC; key="1e3gfc5e-e9f8-4232-a6be-17bf40edad09"; signature="mLtpym3Lgl1300t8cze9wyWOaxkRBKL3j3ztalMjgWs="; date="2015-03-05T02:49:58Z"