Most of the information, I'd say 99% of it, comes from the hard work of Dom Adelard, O.S.B., who was the author of "Dictionnaire des Bouvier" in January 1941-43. Other info has come from other people researching the same families. I guess you could say they are family, eh! As to the book, I have no idea where one can get a copy of it, as I am using a photocopied copy of my uncle's. SHHH!! I didn't just say that did I?
According to the author, Louys (Louis) LeBouvier and Sébastien Bouvier may have been first cousins, and although the two families weave in and out among the many descendants, I think it would be nice if the two families had a closer tie, at the beginning. Dontcha think??
Anyhow, hope you find what you're looking for, and maybe have info to share.