Jens Rösler, son of the last private owner of Montblanc, Dr. Jürgen Rösler (12 March 1930 – 9 September 2003), describes in his "Montblanc Diary & Collector's Guide" the company's history from the founding of the Simplo Filler Pen Company in 1908 through to the Second World War. Substantial parts draw on the recollections of his grandmother Annemarie Rösler, née Voss. The book is illustrated with numerous images of rare writing instruments and period documents and offers detailed descriptions in the appendix of nearly all models produced in this period.
For Montblanc collectors it is currently the only comprehensive reference of its kind and rightly counts as the indispensable bible of pre-war Montblancs. The work is now only available on the collector market and is worth every cent even at prices beyond 250 euros.