Facsimile of the valuable Book of Hours of the Sforza (Volume 1), Add. MS 34294 British Library, London, which was published in 1993 by Faksimile Verlag Luzern.  2 volumes in orig. Velvet cassette (facsimile + commentary volume) Book of Hours comprises 80 pages 44 miniature pages limited to only 980 copies worldwide Copy bears No. 278/980 Format 13.1 x 9.3 cm The Book of Hours is an art-historical rarity because it is a major work by two illuminators, who worked in two different countries and probably never met each other. A story like a thriller. It was only on the basis of coats of arms and inscriptions in the Book of Hours that the original owner of the manuscript could be determined: Bona Sforza, the wife of Galeazzo Maria Sforza, who was Duke of Milan from 1466 to 1476. The first written evidence of the manuscript can be found in a letter sent by the Milanese illuminator Giovan Pietro Birago to an unknown nobleman, in which he writes that parts of an unfinished Book of Hours had been stolen from him by a mendicant monk. These stolen sheets, about a third of the total manuscript, have never reappeared. At the beginning of the 16th century, the still unfinished manuscript passed by inheritance to Margaret of Austria, who conducted the affairs of state for her minor nephew, the later Emperor Charles V. It was not until around 1520 that the missing pages were illuminated, by none other than the court painter Gerard Horenbout. The further history up to the year 1871 is obscure. At that time, an unknown Spanish grandee sold the work through an intermediary to the English conservator Sir John Charles Robinson, from whom it was acquired by the English collector John Malcolm von Poltalloch. He dismantled the manuscript, which had been in one volume until then, and had it bound into four parts