(map subjectScheme)
The %topicref-atts-for-subjectScheme; parameter entity represents the set
of attributes used in the reltable map
element. The set is similar to those documented in topicref-atts but
for <reltable> the toc attribute
defaults to no
. For the other elements that use the %topicref-atts;
group declaration, the toc attribute doesn't have
a default; they can inherit their toc value from
the nearest container, otherwise it functions upon output as if set to yes
.