1. Adams C, Lloyd S (2003) Understanding PKI: concepts, standards, and deployment considerations, 2nd edn, Chap 8. Addison-Wesley, Reading, MA
2. Housley R, Polk T (2001) Planning for PKI: best practices guide for deploying public key infrastructure. Wiley, New York
3. ITU-T Recommendation X.509 (2000). Information technology – open systems interconnection – the directory: Public key and attribute certificate frameworks. (equivalent to ISO/IEC 9594–8:2001)
4. Myers M, Ankney R, Malpani A, Galperin S, Adams C (1999) X.509 Internet public key infrastructure: online certificate status protocol – OCSP. Internet Request for Comments 2560
5. Pinkas D, Housley R (2002) Delegated path validation and delegated path discovery protocol requirements. Internet Request for Comments 3379