[comment {-*- tcl -*- --- doctools ---}]
[vset PACKAGE isbn]
[vset VERSION 1]
[vset A an]
[vset NAME ISBN]
[vset NAMEX ISBN]
[vset CODE ISBN]
[vset OK  ....]
[vset BAD ....]
[vset KEYWORDS k_isbn]
[vset REQUIRE null]
[vset METHODS m_isbn]
[vset CODES c_length]
[include include/vtype.inc]