Elements that can be included along with data characters inside the content model of the <disp-formula> element
<!ENTITY % disp-formula-elements "| %access.class; | %address-link.class; | %break.class; | %emphasis.class; | %inline-display.class; | %inline-math.class; | %label.class; | %math.class; | %simple-display.class; | %subsup.class;" >
math.ent