Imagine that this single bifolium (folded leaf), or to give it its Italian name diploma, is the outermost folded leaf of a quaternion (4on). The slighty shaded page in the background is also a recto page. This shaded page is the penultimate page in the 4on quire, the last but one. Please keep a copy of your answer The last but one page in a 4on quire would be numbered f4r tsvp