ses-formula-references
ses-formula-references is a compiled Lisp function in `ses.el
'.
(ses-formula-references FORMULA &optional RESULT-SO-FAR)
Produce a list of symbols for cells that this FORMULA's value
refers to. For recursive calls, RESULT-SO-FAR is the list being
constructed, or t to get a wrong-type-argument error when the
first reference is found.