Workflow to get Submitted By text translated

I can't get it work on D7, i added to my settings.php at the end of the file:

$conf['i18n_variables'] = array(
  'submitted_by_article',
  'submitted_by_comment_article',
);

And switched the admin site language in the content type edit page after to set the desired text for spanish directly but it just shows me up the text in one language. In this case the last language text i saved under the content type submitted by options.

More details about the workflow to get this done please?

Thanks in advance.