These are 3 examples of the now officially released reading order mechanism for ALTO 4.3.
Is based off of a converted PageXML facsimile of the ONB Newseye dataset. It shows how multiple reading orders for the same page can be encoded: one replicating the complete order described in the original file, and a second one grouping the text blocks into articles.
A single page of BL Add 16406 containing unordered marginalia and interlinear corrections. The latter are encoded in a way that allows extraction of the corrected text, i.e. the level of reading order encoding switches between whole lines and individual words (<String>) in the lines that are corrected.
A single page of Munich Cod hebr. 117 containing a main text with references (paratext) and marginalia. Two reading orders are contained: one separating main text and elements in the margin, and one inserting the paratext and marginal note in the appropriate place in the text flow.