Does this Balzac novel really exist?

I recently read in an article by Michel Butor that a group of 3 novels constitute the "spinal column" of Balzac's Comedie Humaine: Lost Illusions (Illusions Perdues), A Harlot High and Low (Splendeurs et Miseres des Courtisanes) and The Last Incarnation of Vautrin (La Derniere Incarnationde Vautrin). The last mentioned novel doesn't seem to exist, at least not on any listing I can find of Balzac's works! There is a chapter of only around 4 pages late in A Harlot High and Low called "Last Incarnation", but otherwise I find no trace of a novel by such a name. Can anyone solve this mystery for me?

I have studied Balzac pretty much at school and to my memory this kind of a novel doesn`t exist. Maybe it`s a novel Balzac couldn`t finish before he died but that I can`t say for sure. I learned all the titles of Balzac`s novels but that wasn`t among them.
I hope I could be helpful:)

The Last Incarnation of Vautrin as far as I know is not a real book at al....

I have just started to read "A Harlot High and Low" and cannot find the end part mentioning Vautrin - did he use the name Jacques Collin?

My copy of A Harlot High and Low is a Penguin Classic 1970 translated by Rayner Heppenstall and I have just arrived at Part 4 - The Last Incarnation of Vautrin - it goes on for 142 pages and ends with Vautrin retiring with a comfortable legacy- he was certainly a fascinating character and one of the best of Balzac"s creations.