+for ascending order. These apply to all the listed variables
+up until the preceding (A), (D), (UP) or (DOWN).
+
+The sort algorithms used by @cmd{SORT CASES} are stable. That is,
+records that have equal values of the sort variables will have the
+same relative order before and after sorting. As a special case,
+re-sorting an already sorted file will not affect the ordering of
+cases.