A double-biography that might be of interest is Shining As Stars: The Stories of Matt Talbot, the saintly Irish laborer and Leon Dupont, the Holy Man of Tours (with Illustrations) by John Beevers, American edition published by Newman Press, Westminster, Maryland in 1956. Three copies of this out-of-print book are currently for sale on eBay and Amazon.com.
From the front cover flap: "Holiness, while one in essence, finds endlessly varied manifestations in the personalities of those whom grace touches, Alike in their love of God, the saints can be refreshingly unlike one another in almost every other respect. Moulds are carelessly broken, categories lightly transgressed, norms easily surpassed. One may be a saint sitting on a pillar in 5th century Syria, or sitting on a throne in 13th century France...
From the back cover flap: "...John Beevers has traced and compared the lives of Leon Dupont and Matt Talbot. Superficially they were distantly different men: one a wealthy, well educated, traveled, and socially prominent French business man; the other, an obscure Dublin dock-worker, almost without education, certainly without position; his home a tenement room, the extent of his travels the city limits. The Holy Man of Tours, as Leon Dupont came to be known, never had to do a hard day's physical work in his life; Matt Talbot did little else. One was married; the other single. One enjoyed a wide circle of acquaintances; the other hardly had a close friend. But in that incalcuable and startling democracy of holiness these two men were alike. Each in his own fashion, each in his own circumstances, each in his own unique response to the guidance of the Spirit who breathes where He will, these two men achieved that similarity that springs from the stamp of Christlikeness..."
Beevers (1911-1975) wrote a number of books on saints as well as religious and secular topics. It was from research on his previous book on St. Therese of the Child Jesus and her devotion to the Holy Face of Our Lord that led Beevers to a "photograph of the Holy Face," the one venerated by Leon Dupont, and found in a reproduction of a page of Matt Talbot's prayer book, a book which contained eight pages given up to the devotion and included some of the prayers written by M. Dupont" (Shining as Stars, page 10).