diff --git a/Utils/Matrix.ml b/Utils/Matrix.ml
index 7f3aeaa..af537d8 100644
--- a/Utils/Matrix.ml
+++ b/Utils/Matrix.ml
@@ -154,6 +154,7 @@ let mm ?(transa=`N) ?(transb=`N) ?(threshold=epsilon) a b =
   if f a <> f' b then
       invalid_arg "Inconsistent dimensions";
 
+  (* Dense x sparse *)
   let mmsp transa transb a b =
     let a =
       match transa with
@@ -184,6 +185,7 @@ let mm ?(transa=`N) ?(transb=`N) ?(threshold=epsilon) a b =
     Sparse {m=m' ; n ; v=v'}
   in
 
+  (* Sparse x dense *)
   let spmm transa transb a b =
     let b =
       match transb with
@@ -216,6 +218,7 @@ let mm ?(transa=`N) ?(transb=`N) ?(threshold=epsilon) a b =
     Sparse {m ; n=n' ; v=v'}
   in
 
+  (* Sparse x Sparse *)
   let mmspmm transa transb a b = 
     let {m ; n ; v} = 
       if transb = `T then
@@ -331,18 +334,34 @@ let test_case () =
     let x3 = gemm x1 x2 in
     let m3 = dense_of_mat x3
     and m3_s = sparse_of_mat x3
+    and m4 = dense_of_mat x1 |> transpose
+    and m4_s = sparse_of_mat x1 |> transpose
+    and m5 = dense_of_mat x2 |> transpose
+    and m5_s = sparse_of_mat x2 |> transpose
     in
     let norm_diff m1 m2 =
       (Mat.sub (to_mat m1) (to_mat m2)
       |> Mat.syrk_trace)
     in
-    Alcotest.(check (float 1.e-10)) "dense  dense  1" 0. (norm_diff (mm m1 m2) m3);
-    Alcotest.(check (float 1.e-10)) "dense  sparse 2" 0. (norm_diff (mm m1 m2_s) m3_s);
-    Alcotest.(check (float 1.e-10)) "dense  sparse 3" 0. (norm_diff (transpose (mm m2 m1_s ~transa:`T ~transb:`T)) m3_s);
-    Alcotest.(check (float 1.e-10)) "sparse dense  4" 0. (norm_diff (mm m1_s m2) m3_s);
-    Alcotest.(check (float 1.e-10)) "sparse dense  5" 0. (norm_diff (transpose (mm m2_s m1 ~transa:`T ~transb:`T)) m3_s);
-    Alcotest.(check (float 1.e-10)) "sparse sparse 6" 0. (norm_diff (mm m1_s m2_s) m3_s);
-    Alcotest.(check (float 1.e-10)) "sparse sparse 7" 0. (norm_diff (transpose (mm m2_s m1_s ~transa:`T ~transb:`T)) m3_s);
+    Alcotest.(check (float 1.e-10)) "dense  dense   1" 0. (norm_diff (mm m1 m2) m3);
+    Alcotest.(check (float 1.e-10)) "dense  dense   2" 0. (norm_diff (mm ~transa:`T m4 m2) m3);
+    Alcotest.(check (float 1.e-10)) "dense  dense   3" 0. (norm_diff (mm ~transb:`T m1 m5) m3);
+    Alcotest.(check (float 1.e-10)) "dense  dense   4" 0. (norm_diff (mm ~transa:`T ~transb:`T m2 m1) (transpose m3));
+                                                   
+    Alcotest.(check (float 1.e-10)) "dense  sparse  5" 0. (norm_diff (mm m1 m2_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "dense  sparse  6" 0. (norm_diff (mm ~transa:`T m4 m2_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "dense  sparse  7" 0. (norm_diff (mm ~transb:`T m1 m5_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "dense  sparse  8" 0. (norm_diff (transpose (mm m2 m1_s ~transa:`T ~transb:`T)) m3_s);
+
+    Alcotest.(check (float 1.e-10)) "sparse dense   9" 0. (norm_diff (mm m1_s m2) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse dense  10" 0. (norm_diff (mm ~transa:`T m4_s m2) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse dense  11" 0. (norm_diff (mm ~transb:`T m1_s m5) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse dense  12" 0. (norm_diff (transpose (mm m2_s m1 ~transa:`T ~transb:`T)) m3_s);
+
+    Alcotest.(check (float 1.e-10)) "sparse sparse 13" 0. (norm_diff (mm m1_s m2_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse sparse 14" 0. (norm_diff (mm ~transa:`T m4_s m2_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse sparse 15" 0. (norm_diff (mm ~transb:`T m1_s m5_s) m3_s);
+    Alcotest.(check (float 1.e-10)) "sparse sparse 16" 0. (norm_diff (transpose (mm m2_s m1_s ~transa:`T ~transb:`T)) m3_s);
   in
   [
     "Conversion", `Quick, test_conversion;