There’s a Debian package available for Citrix Receiver, so in principle this task should be trivial.
Simply installing the package leaves you with a SSL error whenever you try to connect to a Citrix resource. You need to jump through a couple of extra hoops to get it actually working.
Installing the Package
Download the package from here (scroll down to the “Debian Packages” section).
$ sudo dpkg -i icaclient_22.214.171.124_amd64.deb
Now you need to sort out the SSL certificates.
Sorting the Certificates
Link in the certificates (these should already be resident somewhere on your machine).
$ sudo ln -s /usr/share/ca-certificates/mozilla/* /opt/Citrix/ICAClient/keystore/cacerts/
Create a hash for each certificate.
$ sudo c_rehash /opt/Citrix/ICAClient/keystore/cacerts/
And you are ready to roll! Connect to your Citrix resources. Enjoy.