Z language latex
usepackage{oz, amsfonts}
begin{schema}{MusicStore}
member: pset NAME\
orders: pset (NAMEtimes ALBUM)\
owns: pset (NAMEtimes ALBUM)
ST
{bf dom}mbox{ } orders subseteq member\
{bf dom}mbox{ } owns subseteq member\
forall (m, a)in orders.(m, a)notin owns
end{schema}