question: returns the system id used to resolve external entities . concode_field_sep String FEATURE concode_elem_sep Node node concode_elem_sep String systemId concode_elem_sep Node nextSibling concode_field_sep Node getNextSibling concode_elem_sep void setSystemId concode_elem_sep void setNode concode_elem_sep Node getNode concode_elem_sep void setNextSibling
target: String function ( ) { return systemId ; }