libgnutls28-dev software package provides GNU TLS library - development files, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libgnutls28-dev
libgnutls28-dev is installed in your system.
Make ensure the libgnutls28-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep libgnutls28-dev *
You will get with libgnutls28-dev package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Library development |
| Package | libgnutls28-dev |
| Version | 3.2.11-2ubuntu1.1 [amd64, i386 |
| Description | GNU TLS library - development files |
| Sub Section | libdevel |