diff --git a/src/base/abci/abcNpn.c b/src/base/abci/abcNpn.c
index 92b47c177..ab8a7a685 100644
--- a/src/base/abci/abcNpn.c
+++ b/src/base/abci/abcNpn.c
@@ -319,10 +319,6 @@ void Abc_TruthNpnPerform( Abc_TtStore_t * p, int NpnType, int fVerbose )
     }
     else if ( NpnType == 8 )
     {
-//        typedef unsigned(*TtCanonicizeFunc)(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int flag);
-        unsigned Abc_TtCanonicizeWrap(TtCanonicizeFunc func, Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int flag);
-        unsigned Abc_TtCanonicizeAda(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int iThres);
-		
 		int fHigh = 1, iEnumThres = 25;
 		Abc_TtHieMan_t * pMan = Abc_TtHieManStart(p->nVars, 5);
 		for ( i = 0; i < p->nFuncs; i++ )
@@ -337,11 +333,6 @@ void Abc_TruthNpnPerform( Abc_TtStore_t * p, int NpnType, int fVerbose )
     }
     else if ( NpnType == 9 || NpnType == 10 || NpnType == 11 )
     {
-//        typedef unsigned(*TtCanonicizeFunc)(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int flag);
-        unsigned Abc_TtCanonicizeWrap(TtCanonicizeFunc func, Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int flag);
-        unsigned Abc_TtCanonicizeAda(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int iThres);
-        unsigned Abc_TtCanonicizeCA(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int iThres);
-		
 		Abc_TtHieMan_t * pMan = Abc_TtHieManStart(p->nVars, 5);
 		for ( i = 0; i < p->nFuncs; i++ )
         {
diff --git a/src/opt/dau/dau.h b/src/opt/dau/dau.h
index 82e9b83b2..37d24aa5a 100644
--- a/src/opt/dau/dau.h
+++ b/src/opt/dau/dau.h
@@ -86,6 +86,7 @@ extern Abc_TtHieMan_t * Abc_TtHieManStart( int nVars, int nLevels );
 extern void          Abc_TtHieManStop(Abc_TtHieMan_t * p );
 extern unsigned      Abc_TtCanonicizeWrap(TtCanonicizeFunc func, Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int flag);
 extern unsigned      Abc_TtCanonicizeAda(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int iThres);
+extern unsigned      Abc_TtCanonicizeCA(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int fCA);
 extern unsigned      Abc_TtCanonicizeHie(Abc_TtHieMan_t * p, word * pTruthInit, int nVars, char * pCanonPerm, int fExact);
 /*=== dauCount.c ==========================================================*/
 extern int           Abc_TtCountOnesInCofsQuick( word * pTruth, int nVars, int * pStore );
diff --git a/src/opt/dau/dauNpn.c b/src/opt/dau/dauNpn.c
index f4a4bb531..be9aae3ef 100644
--- a/src/opt/dau/dauNpn.c
+++ b/src/opt/dau/dauNpn.c
@@ -1082,7 +1082,6 @@ Vec_Mem_t * Dau_CollectNpnFunctionsArray( Vec_Wrd_t * vFuncs, int nVars, Vec_Int
 void Dau_CanonicizeArray( Vec_Wrd_t * vFuncs, int nVars, int fVerbose )
 {
     abctime clkStart  = Abc_Clock();
-    extern unsigned Abc_TtCanonicizeCA(Abc_TtHieMan_t * p, word * pTruth, int nVars, char * pCanonPerm, int iThres);
     if ( fVerbose )   printf( "Functions: %d (original) ", Vec_WrdSize(vFuncs) );
     unsigned uCanonPhase; char pCanonPerm[16]; word Func; int i;
     Vec_WrdUniqify( vFuncs );