add apt repository not found

Well I have to admit that it really spent me too much time on configuring the Bumblebee which is said can better manage double video cards situation Bumblebee.
But I can not make a good use of this software because I can not find the command named ‘add-apt-repository’
This time I got to know that this command is accompanied by python software properties, and finally I have these answer from stackoverflow

It introduced two ways of installing this tool. Of which version below 12.10(exclusively),
sudo apt-get install python-software-properties
But as for those version above 12.10(inclusively),
sudo apt-get install software-properties-common
And now I am going to configuration procedure of double video cards!