A Visual Language for XML Martin Erwig Oregon State University [email protected] posed language, however, relying on the presence of DTDs could be in many cases prohibitive. Second, we do not want to require users of the language to have knowledge of the concept of a “schema”. Nevertheless, there are ways to nicely exploit DTDs when they are given. We shall discuss this issue in Section 5. Let us consider a small example. Below we show some bibliographic data in XML format.  !"!$#&%'(*)"+,-$."//,$ *001'*2!34)"'0'65(*07'98(*0"4:";*001' "(