$ sudo apt-get update
$ sudo apt-get install dolphin-owncloud 

dolphin-owncloud is installed in your system.

Make ensure the dolphin-owncloud package were installed using the commands given below,

$ sudo dpkg-query -l | grep dolphin-owncloud *

You will get with dolphin-owncloud package name, version, architecture and description in a table

dolphin-owncloud package basic information: