This is an APT repository for the PTERM software, originally from CYBER1.ORG.. These have been packaged to be easy to install on Raspbian.
APT source lines for each Raspbian repository are below:
sudo echo "deb http://rpi.irata.online/ jessie main" >/etc/sources.list.d/pterm.list
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 5E67E0B4
sudo apt-get install pterm
sudo echo "deb http://rpi.irata.online/ stretch main" >/etc/sources.list.d/pterm.list
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 5E67E0B4
sudo apt-get install pterm