Use only letters, numbers and the following characters: : ; , . ? ! &lsqb#lbrack; &rsqb#rbrack; ( ) `` ∼ - / *
If Marker Fields are turned on from the View menu, markers appear on the screen as small gray boxes containing the word ``marker`` and the key for the item. You can toggle on and off the display of markers from the View menuView_menu_commands.tex.
If Marker Fields are turned on in the Print OptionsPrint_options.tex, markers appear in print.