ferret software package provides CASE tool for data model editing, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install ferret
ferret is installed in your system.
Make ensure the ferret package were installed using the commands given below,
$ sudo dpkg-query -l | grep ferret *
You will get with ferret package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Miscellaneous |
| Package | ferret |
| Version | 0.6-5 |
| Description | CASE tool for data model editing |
| Sub Section | Misc |