Go to: https://www.citrix.com/downloads/citrix-receiver/linux/receiver-for-linux-latest.html

Receiver 13.4 for Linux

Expand: Debian Packages

Click (to download):

Full Package (Self-Service Support) > Receiver for Linux (x86_64)

Read: End-User License Agreement

Click: "Yes, I accept"

Download: icaclient13.5.0.10185126amd64.deb

Click to install with Software Installer

When you get: SSL error

(from: https://www.guyrutenberg.com/2012/12/22/installing-citrix-receiver-on-ubuntu-64bit/)

issue this command:

sudo mv /usr/share/ca-certificates/mozilla/AddTrust_External_Root.crt /opt/Citrix/ICAClient/keystore/cacerts/