-AGE must be one of the symbols 'old or 'immortal.
-TITLE-OR-DESCRIPTION must be on of the symbols 'title,
-'description, or 'all. REGEXP is a regular expression, i.e. a
+AGE must be one of the symbols `old' or `immortal'.
+TITLE-OR-DESCRIPTION must be one of the symbols `title',
+`description', or `all'. REGEXP is a regular expression, i.e., a