Julian Graham has posted SDOM 0.1.2, a DOM Level 3 implementation for Scheme. This is designed as an extension of Oleg Kiselyov's SXML. According to Kiselyov, "SXML is an abstract syntax tree of an XML document. SXML is also a concrete representation of the XML Infoset in the form of S-expressions." SDOM is free software, published under the GPL.