Cant modify copyright info

I want to put a "." (dot) after "Designed by ThemeSquirrel, thanks to: ketones UK, Free Directory and cd-bar.com" so its going to look like this: "Designed by ThemeSquirrel, thanks to: ketones UK, Free Directory and cd-bar.com.".
I tried modifying the code from this:
<a href='http://cd-bar.com' target='_blank'>cd-bar.com</a></div>

to this adding the dot after </a> :

<a href='http://cd-bar.com' target='_blank'>cd-bar.com</a>.</div>

I get the following message when I enter the website:

"Please return following links to the footer:
Designed by ThemeSquirrel, thanks to: ketones UK, Free Directory and cd-bar.com"

Tell me please how can I put the dot after the sentence. Every sentence should end with a DOT.

Hi!
You are not allowed to change the links in the footer. Even if you are going just to add dot. This is not possible.