[1] [CITE@ja[Sender Policy Framework - Wikipedia]]
([TIME[2009-09-27 09:05:23 +09:00]] 版)
<http://ja.wikipedia.org/wiki/Sender_Policy_Framework>

[6] [CITE@en[RFC 4408: Sender Policy Framework (SPF) for Authorizing Use of Domains in E-Mail, Version 1]], [TIME[2023-12-02T08:31:40.000Z]], [TIME[2023-12-02T08:51:42.704Z]] <https://www.rfc-editor.org/rfc/rfc4408.html>

[10] [CITE[RFC Errata Report » RFC Editor]], [TIME[2023-12-02T08:54:57.000Z]] <https://www.rfc-editor.org/errata/rfc4408>

[2] [CITE@en[RFC 6577 - Authentication-Results Registration Update for Sender Policy Framework (SPF) Results]]
( ([TIME[2012-07-02 02:43:00 +09:00]] 版))
<http://tools.ietf.org/html/rfc6577>

[3] [CITE@en[RFC 6652 - Sender Policy Framework (SPF) Authentication Failure Reporting Using the Abuse Reporting Format]]
( ([TIME[2012-08-16 05:09:52 +09:00]] 版))
<http://tools.ietf.org/html/rfc6652>

[4] [CITE@en[RFC 6686 - Resolution of the Sender Policy Framework (SPF) and Sender ID Experiments]]
( ([TIME[2012-07-21 03:14:53 +09:00]] 版))
<http://tools.ietf.org/html/rfc6686>

[5] [CITE@en-US[Fix "CharacterStringTooLong" Errors When Creating TXT Records]]
([TIME[2019-01-10 12:49:21 +09:00]])
<https://aws.amazon.com/jp/premiumsupport/knowledge-center/characterstringtoolong-error/>

[7] [CITE@en[RFC 4406: Sender ID: Authenticating E-Mail]], [TIME[2023-12-02T08:31:42.000Z]], [TIME[2023-12-02T08:54:17.765Z]] <https://www.rfc-editor.org/rfc/rfc4406.html>


[8] [CITE@en[RFC 4407: Purported Responsible Address in E-Mail Messages]], [TIME[2023-12-02T08:31:41.000Z]], [TIME[2023-12-02T08:54:32.151Z]] <https://www.rfc-editor.org/rfc/rfc4407.html>

[9] [CITE[RFC Errata Report » RFC Editor]], [TIME[2023-12-02T08:54:41.000Z]] <https://www.rfc-editor.org/errata/rfc4407>

[11] [CITE@en[RFC 4405: SMTP Service Extension for Indicating the Responsible Submitter of an E-Mail Message]], [TIME[2023-12-02T08:55:42.000Z]], [TIME[2023-12-02T08:56:05.931Z]] <https://www.rfc-editor.org/rfc/rfc4405.html>

[12] 
[CITE@ja[SPF レコードを定義する: 基本設定 - Google Workspace 管理者 ヘルプ]], [TIME[2024-03-21T08:09:56.000Z]] <https://support.google.com/a/answer/10685031?hl=ja>