A book published in 1943 by Joseph Martin Feely giving his solution to the authorship of the Voynich Manuscript, following the thesis, originally propounded by Raphael Mnishovsky, and which was then taken up by Wilfrid Voynich that Roger Bacon was the document's author.
John Tiltman dismissed the book, stating that Feely's method was unmethodical and produced bad Latin.
Some detail can be found here, here and here.
The vellum of the manuscript has been dated to long after Roger Bacon's time (1219/20 – c 1292) and he had little connection with Italy.