diff --git a/src/ODE/ODESolvers/SIBS/SIBS.C b/src/ODE/ODESolvers/SIBS/SIBS.C
index 99b03346b5..ec5c196ff0 100644
--- a/src/ODE/ODESolvers/SIBS/SIBS.C
+++ b/src/ODE/ODESolvers/SIBS/SIBS.C
@@ -71,8 +71,8 @@ void Foam::SIBS::solve
     const ODE& ode,
     scalar& x,
     scalarField& y,
-    scalarField& dydx, 
-    const scalar eps, 
+    scalarField& dydx,
+    const scalar eps,
     const scalarField& yScale,
     const scalar hTry,
     scalar& hDid,
@@ -96,7 +96,7 @@ void Foam::SIBS::solve
         {
             for (register label k=0; k<iq; k++)
             {
-                alpha_[k][iq] = 
+                alpha_[k][iq] =
                     pow(eps1, (a_[k + 1] - a_[iq + 1])
                    /((a_[iq + 1] - a_[0] + 1.0)*(2*k + 3)));
             }
diff --git a/src/ODE/ODESolvers/SIBS/SIBS.H b/src/ODE/ODESolvers/SIBS/SIBS.H
index 03e3535bdf..ff08b81ac9 100644
--- a/src/ODE/ODESolvers/SIBS/SIBS.H
+++ b/src/ODE/ODESolvers/SIBS/SIBS.H
@@ -29,8 +29,8 @@ Description
     Foam::SIBS
 
 SourceFiles
-    SIBSCK.C
-    SIBSQS.C
+    SIMPR.C
+    polyExtrapolate.C
 
 \*---------------------------------------------------------------------------*/
 
@@ -61,7 +61,7 @@ class SIBS
 
         mutable scalarField a_;
         mutable scalarSquareMatrix alpha_;
-        mutable scalarSquareMatrix d_p_;
+        mutable scalarRectangularMatrix d_p_;
         mutable scalarField x_p_;
         mutable scalarField err_;
 
@@ -75,30 +75,31 @@ class SIBS
         mutable scalar epsOld_, xNew_;
 
 
-void SIMPR
-(
-    const ODE& ode,
-    const scalar xStart,
-    const scalarField& y,
-    const scalarField& dydx,
-    const scalarField& dfdx,
-    const scalarSquareMatrix& dfdy,
-    const scalar deltaX,
-    const label nSteps,
-    scalarField& yEnd
-) const;
+    // Private member functions
 
+        void SIMPR
+        (
+            const ODE& ode,
+            const scalar xStart,
+            const scalarField& y,
+            const scalarField& dydx,
+            const scalarField& dfdx,
+            const scalarSquareMatrix& dfdy,
+            const scalar deltaX,
+            const label nSteps,
+            scalarField& yEnd
+        ) const;
 
-void polyExtrapolate
-(
-    const label iest,
-    const scalar xest,
-    const scalarField& yest,
-    scalarField& yz,
-    scalarField& dy,
-    scalarField& x_p,
-    scalarSquareMatrix& d_p
-) const;
+        void polyExtrapolate
+        (
+            const label iest,
+            const scalar xest,
+            const scalarField& yest,
+            scalarField& yz,
+            scalarField& dy,
+            scalarField& x_p,
+            scalarRectangularMatrix& d_p
+        ) const;
 
 
 public:
diff --git a/src/ODE/ODESolvers/SIBS/polyExtrapolate.C b/src/ODE/ODESolvers/SIBS/polyExtrapolate.C
index a9c93329d6..6a05e1600a 100644
--- a/src/ODE/ODESolvers/SIBS/polyExtrapolate.C
+++ b/src/ODE/ODESolvers/SIBS/polyExtrapolate.C
@@ -36,7 +36,7 @@ void Foam::SIBS::polyExtrapolate
     scalarField& yz,
     scalarField& dy,
     scalarField& x,
-    scalarSquareMatrix& d
+    scalarRectangularMatrix& d
 ) const
 {
     label n = yz.size();