closed Archaeological Markup Language (ArchaeoML), version 0.9, February 2006. Created by David Schloen of the University of Chicago. Relationship document type. A Relationship document represents a conceptual relationship between two entities (each represented by an ArchaeoML document). The startNodeID and endNodeID elements contain the UUIDs of the related documents. A model of relationships (graph of entities) is represented by a Tree document that organizes Relationship documents.