[1] 
<http://www.nttdocomo.co.jp/service/imode/make/content/browser/html/tag/tel.html>

[2] 
<http://www.nttdocomo.co.jp/service/imode/make/content/browser/html/tag/tel-av.html>

[3] telbook cannot contain emoji symbols; kana can only contain
halfwidth katakana characters; they have length constraint