15. 參考:
● 事件監聽器:
https://support.google.com/tagmanager/answer/3415369?hl=zh-Hant
● How to Fire a Virtual Pageview in Google Tag Manager:
http://www.lunametrics.com/blog/2014/09/10/fire-virtual-pageview-google-tag-manager/#sr=g&m=o&cp=or&ct=-
tmc&st=(opu%20qspwjefe)&ts=1418637831
● Event Tracking in Google Analytics Universal through Google
Tag Manager:
https://www.youtube.com/watch?v=-H_TikHFfso