The OpenSSH and OpenSSL projects are in constant development, and the most up-to-date information for them is available from their websites. The man pages for OpenSSH and OpenSSL tools are also good sources of detailed information.
8.8.1. Installed Documentation
The ssh, scp, sftp, sshd, and ssh-keygen man pages — These man pages include information on how to use these commands as well as all the parameters that can be used with them.