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Baltimore, Walters Art Museum, MS. W.258 is an unusual Prayerbook with dozens of prayers, and indulgences totalling over 13,500 years. For a detailed description see Lilian M.C. Randall, Medieval and Renaissance Manuscripts in the Walters Art Gallery, Volume II: France, 1420–1540 (2 vols, Baltimore and London, 1992), II, cat.no.169, from which the two images above are scanned.
Although the script is different, and the leaf-size somewhat different, in other respects the two books could almost be twins.