Dot Porter, Curator, Digital Research Services at the University of Pennsylvania Library, offers a video orientation to Penn Library’s LJS 312, a mathematical work on basic calculations, including business or commercial arithmetic. It was written in Hebrew, in Spain, in the 15th century.
You can read the complete record for this document (and find links to digitized copies) on Franklin. You can also download a copy of this video from ScholarlyCommons, the University of Pennsylvania’s open access institutional repository.
The Schoenberg Institute for Manuscript Studies 