“…In [Aiello et al, 2002] we presented a system which, by using spatial reasoning [Aiello and Smeulders, 2004] and text processing techniques [Sparck Jones, 1972, Salton and McGill, 1983, Baeza-Yates and Ribeiro-Neto, 1999, is able to extract the reading order from document images for documents having very different layouts. In particular, a spatial language for rectangles [Balbiani et al, 1998], based on the work on interval relations of Allen [Allen, 1983], is used to describe both the elements in a document and general rules to analyze them.…”