RedHat provides an extensive explanation of certificates, what they are, and how they authenticate web sites, servers, clients, or people.
The Linux Documentation Project provides a “how to” about SSL certificates.
Durumeric, Kasten, Bailey, and Halderman presented 2013 results of a large-scale analysis of certificates actively used by SSL/TLS sites.
Describes how web browsers handle the multitude of certificate authorities used today to sign web server certificates.
Video notes: cys.me/vid/c14
Video #15 explains intermediate certificate authorities, authority delegation, and the certificate chaining process
The previous video describes public-key certificate validation vimeo.com/208879048
See the entire Cryptosmith series in its album vimeo.com/album/4229550