[1] Extended Contact Attributes - Google Talk for Developers - Google Code ( 版) http://code.google.com/intl/ja/apis/talk/jep_extensions/roster_attributes.html

[2]

xmlns:gr='google:roster'

[3] Forrest はGoogle検索の意味で使っています。

[4] Sitelinks Search Box  |  Structured Data  |  Google Developers ( 版) https://developers.google.com/structured-data/slsb-overview

To tell Google not to show a Sitelinks search box when your site appears in the search results, add the following meta tag to your homepage:

<meta name="google" content="nositelinkssearchbox" />

[5] Firebase Cloud Messaging サーバーについて  |  Firebase ( ()) https://firebase.google.com/docs/cloud-messaging/server

次に、送信後同期メッセージの単純な XMPP スタンザを示します。

<message id="">

<gcm xmlns="google:mobile:data">