Erik Siegel's Schematron: A Language for Validating XML is out now from XML Press, as paperback (260 pages, nicely set on good wide pages, lays flat fairly well), eBook, .mobi (Kindle) and PDF. It features the Schematroll on the cover.
It fills in a big gap, and congratulations to Erik for a well written and thorough work. It goes through each element and attribute, and has a primer in XPath.
(Of course, if you want to pay 8 times more for a book 8 times smaller, you can get the ISO Standard!)
I have a little review at Schematron.com.
Cheers,
Rick
