Email Formats

{
  "mx": [
    "10 mx1.mail.yahoo.co.jp.",
    "10 mx3.mail.yahoo.co.jp.",
    "10 mx2.mail.yahoo.co.jp.",
    "10 mx5.mail.yahoo.co.jp."
  ],
  "spf": [
    "v=spf1 include:spf.yahoo.co.jp ~all"
  ]
}