Treaty of Verdun 843

I was wondering of there is actually an original text of this Treaty, or is it only known through later versions? Are there any books written specifically on this Treaty, its precursors and consequences? Any information on the internet would be welcome as well.

Contemporary sources:

• Annales Bertiniani
• Regino's Chronicon

Anything on the later Carolingians should talk about it. There will be more in French and German. For example, Theodor Mayer (ed.), Der Vertrag von Verdun 843; Neun Aufsätze zur Begründung der europäischen Völkerund Staatenwelt, Leipzig 1963. So long as you don't mind reading something from someone who collaborated extensively with the Nazi's during WWII.

Online in English: http://oll.libertyfund.org/?option=com_staticxt&staticfile=show.php%3Ftitle=...

Dutton's "Carolingian Reader has a good translation into English, and a great deal more on the Carolingians as a whole.