--- mathml.spad.pamphlet-old	2009-10-21 13:59:54.000000000 -0700
+++ mathml.spad.pamphlet	2010-02-08 10:12:20.000000000 -0800
@@ -974,6 +974,19 @@
       -- {{CONCAT}{,}{1}}}{{CONCAT}{,}{2}}}{{CONCAT}{,}{1}}}}{x}{z}},
       -- here expr is everything in the first set of braces and
       -- args is {{x}{z}}
+      -- 2010-02-08:  subscripts can also be produced by, e.g., a[1,2]
+      -- so I now test for the presence of 'CONCAT' in expr to see if
+      -- it's really a partial derivative, a hack for now.
+      position("CONCAT",stringify expr,1) = 0 =>
+        tmp : S := formatMml(first args, 0)
+        s : S := concat ["<msub>" tmp "<mrow>"]
+        args := rest args
+        while not(null(args)) repeat
+          tmp := formatMml(first args, 0)
+          s := concat [s tmp]
+          if #args > 1 then s:= concat [s "<mo>,</mo>"]
+          args := rest args
+        s := concat [s "</mrow></msub>"]
       atomE : L E := atomize(expr)
       op : S := stringify first atomE
       op ~= "SUB" => "<mtext>Mistake in formatSub: no SUB</mtext>"