of blackboard bold for the index, he produced using the letters and with a negative space between; in 1988 Robert Messer extended this to a full set of "poor man's blackboard bold" macros, overtyping each capital letter with carefully placed characters or vertical lines.

Not all mathematical authors were satisfied with such workarounds. The American Mathematical Society created a simple chalk-style blackboard bold typeface in 1985 to go with the AMS-TeX