[1] WebTrust Program for Certification Authorities | Chartered Accountants of Canada ( 版) <http://www.webtrust.org/homepage-documents/item27839.aspx>
[2] WebTrustSM/TM Program for Certification Authorities ( 版) <http://www.webtrust.org/homepage-documents/item65306.pdf>
[3] Trust Service Principles and Criteria for Certification Authorities ( 版) <http://www.webtrust.org/homepage-documents/item54279.pdf>