apt-src software package provides manage Debian source packages, 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 apt-src
apt-src is installed in your system.
Make ensure the apt-src package were installed using the commands given below,
$ sudo dpkg-query -l | grep apt-src *
You will get with apt-src package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Administration Utilities |
| Package | apt-src |
| Version | 0.25.1-0.2 |
| Description | manage Debian source packages |
| Sub Section | admin |