This Technical Report provides a DSSSL library that can specify styles for the documents described by SGML (Standard Generalized Markup Language@ ISO 8879) or XML (Extensible Markup Language@ W3C REC-xml- 980210). The library makes it feasible to describe DSSSL specification for those documents@ without any particular knowledge of DSSSL or particular composition rules. The library deals with some complex compositions described by a number of complicated DSSSL specification statements. They are typically required in fixed-pitch document styles. Some of them can be applied to proportional pitch styles and fixed/proportional mixtures as well. More sophisticated compositions will be dealt with in a future Technical Report to be submitted.