diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,5 +1,10 @@
 ## Changes in version 0.2.1
 
+* Fixed #2. Another bug that resulted in incorrect results
+  for some inputs.
+
+## Changes in version 0.2.1
+
 * Fixed a bug that resulted in incorrect results.
 
 ## Changes in version 0.2.0
diff --git a/Data/Graph/Dom.hs b/Data/Graph/Dom.hs
--- a/Data/Graph/Dom.hs
+++ b/Data/Graph/Dom.hs
@@ -151,9 +151,9 @@
   n <- gets dfsE
   forM_ [n,n-1..1] (\i-> do
     w <- ndfsM i
-    sw <- sdnoM w
     ps <- predsM w
     forM_ ps (\v-> do
+      sw <- sdnoM w
       u <- eval v
       su <- sdnoM u
       when (su < sw)
@@ -290,9 +290,10 @@
 
 initEnv :: Rooted -> ST s (Env s)
 initEnv (r0,g0) = do
+  -- Graph renumbered to indices from 1 to |V|
   let (g,rnmap) = renum 1 g0
-      pred      = predG g
-      r         = rnmap IM.! r0
+      pred      = predG g -- reverse graph
+      root      = rnmap IM.! r0 -- renamed root
       n         = IM.size g
       ns        = [0..n]
       m         = n+1
@@ -314,13 +315,14 @@
   ndfs      <- newI m
   dfn       <- newI m
 
+  -- Initialize all arrays
   forM_ [0..n] (doms.=0)
   forM_ [0..n] (sdno.=0)
   forM_ [1..n] (size.=1)
   forM_ [0..n] (ancestor.=0)
   forM_ [0..n] (child.=0)
 
-  (doms.=r) r
+  (doms.=root) root
   (size.=0) 0
   (label.=0) 0
 
@@ -328,7 +330,7 @@
     {rnE        = rna
     ,dfsE       = 0
     ,zeroE      = 0
-    ,rootE      = r
+    ,rootE      = root
     ,labelE     = label
     ,parentE    = parent
     ,ancestorE  = ancestor
@@ -399,6 +401,7 @@
 infixl 9 !:
 infixr 2 .=
 
+-- | arr .= x idx => write x to index
 (.=) :: (MArray (A s) a (ST s))
      => Arr s a -> a -> Int -> ST s ()
 (v .= x) i = unsafeWrite v i x
@@ -531,6 +534,10 @@
 --                                   (f a)
 --                                   (g a) m) mempty
 
+-- | renum n g: Rename all nodes
+--
+-- Gives nodes sequential names starting at n.
+-- Returns the new graph and a mapping.
 -- (renamed, old -> new)
 renum :: Int -> Graph -> (Graph, NodeMap Node)
 renum from = (\(_,m,g)->(g,m))
@@ -555,6 +562,7 @@
 
 -----------------------------------------------------------------------------
 
+-- Nothing better than reinvinting the state monad.
 newtype S z s a = S {unS :: forall o. (a -> s -> ST z o) -> s -> ST z o}
 instance Functor (S z s) where
   fmap f (S g) = S (\k -> g (k . f))
diff --git a/Data/Graph/Dom/Internal.hs b/Data/Graph/Dom/Internal.hs
new file mode 100644
--- /dev/null
+++ b/Data/Graph/Dom/Internal.hs
@@ -0,0 +1,22 @@
+module Data.Graph.Dom.Internal where
+
+import Data.Graph.Dom as D
+
+import Data.Foldable as F
+import Data.List
+import Data.IntMap.Strict as IM
+import Data.IntSet as IS
+
+newline :: [Char]
+newline = "\n"
+
+-- | For debugging only
+asDotFile :: D.Graph -> String
+asDotFile g =
+    let pprNode :: (Int, IntSet) -> String
+        pprNode (node,targets) =
+            concat $ intersperse newline $ fmap (pprEdge node) $ IS.toList targets
+        pprEdge v u = show v ++ " -> " ++ show u ++ ";"
+    in "digraph G {" ++ newline ++
+            (concat $ intersperse newline $ fmap pprNode (IM.toList g)) ++ newline ++
+            "}"
diff --git a/dom-lt.cabal b/dom-lt.cabal
--- a/dom-lt.cabal
+++ b/dom-lt.cabal
@@ -1,8 +1,7 @@
 name:               dom-lt
-version:            0.2.1
+version:            0.2.2
 cabal-version:      >= 1.10
 build-type:         Simple
-tested-with:        GHC == 8.10.1 || == 8.8.4 || == 8.0.1
 license:            BSD3
 license-file:       LICENSE
 category:           Algorithms, Graphs
@@ -17,6 +16,11 @@
 
     Included are ways to compute domination and post-domination relationships.
 
+tested-with:
+  GHC == 8.10.1 || == 8.10.2,
+  GHC == 8.8.4  || == 8.8.3,
+  GHC == 8.0.1
+
 Extra-Source-Files:
   Changelog.md
 
@@ -36,7 +40,9 @@
       base >= 4.9 && < 5
     , array
     , containers >= 0.5 && < 0.7
-  exposed-modules:  Data.Graph.Dom
+  exposed-modules:
+    Data.Graph.Dom,
+    Data.Graph.Dom.Internal
 
 test-suite dom-lt-tests
   Default-Language: Haskell2010
diff --git a/tests/Main.hs b/tests/Main.hs
--- a/tests/Main.hs
+++ b/tests/Main.hs
@@ -7,20 +7,7 @@
 import System.Exit
 
 import Test.HUnit hiding (Node,Path)
--- import Test.Framework.Providers.QuickCheck2
--- import Test.QuickCheck (Property, (===))
--- import Test.QuickCheck.Function (Fun, apply)
--- import Test.QuickCheck.Poly (A, OrdA, B, OrdB, C)
 
--- main = defaultMain
---   [ test_dom
---   , testtest_pdom
---   , test_idom
---   , test_ipdom
---   , test_domTree
---   , test_pdomTree
---   ]
-
 g0 :: Graph
 g0 = fromAdj
   [(1,[2,3])
@@ -46,13 +33,18 @@
   ,(7,[])]
 
 main = do
-  counts <- runTestTT tests
-  putStrLn $ showCounts counts
-  if (errors counts + failures counts) > 0
+  result_counts <- runTestTT tests
+  putStrLn $ showCounts result_counts
+  if (errors result_counts + failures result_counts) > 0
     then exitWith $ ExitFailure 1
     else exitWith   ExitSuccess
 
-tests = TestList $ map TestCase [dom0, dom1, pdom0, pdom1, ipdom0, ipdom1, dom_t_g0, dom_t_g1, dom_pt_g0, dom_pt_g1]
+tests :: Test
+tests =
+  TestList $
+    map TestCase
+      [dom0, dom1, pdom0, pdom1, ipdom0, ipdom1, dom_t_g0, dom_t_g1, dom_pt_g0, dom_pt_g1,
+       dom_T2_g3]
 
 g0_rooted, g1_rooted :: Rooted
 g0_rooted = (1,g0)
@@ -98,7 +90,15 @@
               (  Node {rootLabel = 0, subForest = []}  )
               (pdomTree g1_rooted)
 
+g3_edges :: Graph
+g3_edges = fromAdj [(0,[3,6]), (3,[8,9]), (6,[99]), (8,[11]), (9,[16]), (11,[99]), (12,[99]), (13,[99]), (16,[12,13]), (99,[])]
+g3 :: (Int, Graph)
+g3 = (0 :: Int, g3_edges)
 
+dom_T2_g3 :: Assertion
+dom_T2_g3 = assertEqual "dom #2"
+              [(99,[0])]
+              ( filter (\x -> fst x == 99) $ dom g3)
 
 
 -- applyDomFunctions :: Rooted