dtd-ead software package provides Encoded Archival Description Document Type Definition, you can install in your Ubuntu 12.04 LTS (Precise Pangolin) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dtd-ead
dtd-ead is installed in your system.
Make ensure the dtd-ead package were installed using the commands given below,
$ sudo dpkg-query -l | grep dtd-ead *
You will get with dtd-ead package name, version, architecture and description in a table
| Distro | Ubuntu 12 04 lts precise pangolin |
| Section | Text Processing |
| Package | dtd-ead |
| Version | 2002-1 |
| Description | Encoded Archival Description Document Type Definition |
| Sub Section | Text |