diff --git a/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/PDRDragModel/PDRDragModel.H b/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/PDRDragModel/PDRDragModel.H
index 02a8214cb231c43f2bad39f9142d0c90e4f05daf..8fdf1f8c708e885048ea6a5a776f52074dcef923 100644
--- a/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/PDRDragModel/PDRDragModel.H
+++ b/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/PDRDragModel/PDRDragModel.H
@@ -26,7 +26,8 @@ Class
     Foam::PDRDragModel
 
 Description
-    Base-class for sub-grid obstacle drag models.
+    Base-class for sub-grid obstacle drag models. The available drag model is at
+    \link basic.H \endlink.
 
 SourceFiles
     PDRDragModel.C
diff --git a/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H b/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H
index d3044dec21f326aff7adc0d4ef5cba58417220dc..727cdd9f4c10a08585da71e7b0cafd687c1ed48d 100644
--- a/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H
+++ b/applications/solvers/combustion/PDRFoam/PDRModels/dragModels/basic/basic.H
@@ -70,7 +70,7 @@ Description
         \f$ T \f$ is a tensor in the file CT.
 
     The term \f$ G_{R} \f$ is treated explicitly in the \f$ \kappa-\epsilon
-    \f$ Eqs in the PDRkEpsilon.C file.
+    \f$ Eqs in the \link PDRkEpsilon.C \endlink file.
 
 
 SourceFiles
diff --git a/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.C b/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.C
index 5adde282fa0bbea579e468432d4d2b175703146a..eaaafc99d4ef8e876a50fe691dde5e6495809c84 100644
--- a/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.C
+++ b/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.C
@@ -50,7 +50,7 @@ PDRkEpsilon::PDRkEpsilon
     const volScalarField& rho,
     const volVectorField& U,
     const surfaceScalarField& phi,
-    const basicThermo& thermophysicalModel
+    basicThermo& thermophysicalModel
 )
 :
     RASModel(typeName, rho, U, phi, thermophysicalModel),
diff --git a/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.H b/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.H
index db2bc94c45c9063f7e2d33579cfc62e3a635cb4b..0866a28a8e750cd1af25e973d8d4d06de0d7b033 100644
--- a/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.H
+++ b/applications/solvers/combustion/PDRFoam/PDRModels/turbulence/PDRkEpsilon/PDRkEpsilon.H
@@ -27,7 +27,7 @@ Class
 
 Description
     Standard k-epsilon turbulence model with additional source terms
-    corresponding to PDR basic drag model (basic.H)
+    corresponding to PDR basic drag model (\link basic.H \endlink)
 
     The turbulence source term \f$ G_{R} \f$ appears in the
     \f$ \kappa-\epsilon \f$ equation for the generation of turbulence due to
@@ -93,7 +93,7 @@ public:
             const volScalarField& rho,
             const volVectorField& U,
             const surfaceScalarField& phi,
-            const basicThermo& thermophysicalModel
+            basicThermo& thermophysicalModel
         );
 
 
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEBlendXiEq/SCOPEBlendXiEq.H b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEBlendXiEq/SCOPEBlendXiEq.H
index 50595ff026b7b7c67501ab1c3c1664b2e1f040d1..6f60c3e8cb5f061dbe0447f60a8cf8eb00d651f7 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEBlendXiEq/SCOPEBlendXiEq.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEBlendXiEq/SCOPEBlendXiEq.H
@@ -26,6 +26,10 @@ Class
     Foam::XiEqModels::SCOPEBlend
 
 Description
+    Simple SCOPEBlendXiEq model for XiEq based on SCOPEXiEqs correlation
+    with a linear correction function to give a plausible profile for XiEq.
+    See \link SCOPELaminarFlameSpeed.H \endlink for details on the SCOPE
+    laminar flame speed model.
 
 SourceFiles
     SCOPEBlend.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEXiEq/SCOPEXiEq.H b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEXiEq/SCOPEXiEq.H
index ce756ce016132583c86e118c6e53b7893960eb32..91d3a0f519cb354987296d9d70f0a35a9e39e962 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEXiEq/SCOPEXiEq.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/SCOPEXiEq/SCOPEXiEq.H
@@ -28,6 +28,8 @@ Class
 Description
     Simple SCOPEXiEq model for XiEq based on SCOPEXiEqs correlation
     with a linear correction function to give a plausible profile for XiEq.
+    See \link SCOPELaminarFlameSpeed.H \endlink for details on the SCOPE laminar
+    flame speed model.
 
 SourceFiles
     SCOPEXiEq.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/XiEqModel/XiEqModel.H b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/XiEqModel/XiEqModel.H
index 30f548d91c63f6d8a07198c8eee7346c8447f989..f7f9c798e5f2a7d13486c1c4369cf06c35158238 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/XiEqModel/XiEqModel.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/XiEqModel/XiEqModel.H
@@ -27,6 +27,12 @@ Class
 
 Description
     Base-class for all XiEq models used by the b-XiEq combustion model.
+    The available models are :
+                                \link basicXiSubXiEq.H \endlink
+                                \link Gulder.H \endlink
+                                \link instabilityXiEq.H \endlink
+                                \link SCOPEBlendXiEq.H \endlink
+                                \link SCOPEXiEq.H \endlink
 
 SourceFiles
     XiEqModel.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/instabilityXiEq/instabilityXiEq.H b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/instabilityXiEq/instabilityXiEq.H
index 11c1bc36b29411433f286b1cd590ec047e0b46ab..0f7f7e0557312828b47ef842d3cec56dc1901632 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/instabilityXiEq/instabilityXiEq.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiEqModels/instabilityXiEq/instabilityXiEq.H
@@ -26,6 +26,9 @@ Class
     Foam::XiEqModels::instability
 
 Description
+    This is the equilibrium level of the flame wrinkling generated by
+    inestability. It is a constant (default 2.5). It is used in
+    \link XiModel.H \endlink.
 
 SourceFiles
     instability.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/KTS/KTS.H b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/KTS/KTS.H
index 95028a4d9f8b2041aed98585576c3c83c8318982..2ca885d56784a5e21346108445498dd77b222991 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/KTS/KTS.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/KTS/KTS.H
@@ -26,7 +26,8 @@ Class
     Foam::XiGModels::KTS
 
 Description
-    Simple Kolmogorov time-scale model for the flame-wrinling generation rate.
+    Simple Kolmogorov time-scale (KTS) model for the flame-wrinling generation
+    rate.
 
 SourceFiles
     KTS.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/XiGModel/XiGModel.H b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/XiGModel/XiGModel.H
index 953297d8e65a920800689c12a9e352d594b9f7b7..4e6ee553bbe139e58a36b810ade9544ad2462f37 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/XiGModel/XiGModel.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/XiGModel/XiGModel.H
@@ -27,6 +27,9 @@ Class
 
 Description
     Base-class for all Xi generation models used by the b-Xi combustion model.
+    See Technical Report SH/RE/01R for details on the PDR modelling. For details
+    on the use of XiGModel see \link XiModel.H \endlink. The model available is
+    \link instabilityG.H \endlink
 
 SourceFiles
     XiGModel.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/instabilityG/instabilityG.H b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/instabilityG/instabilityG.H
index ac63d1833db1c40d65c75cc55f1308aeb6a75a8e..ab01b3a8e030e518790a03d9195fdfe653231d3f 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/instabilityG/instabilityG.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiGModels/instabilityG/instabilityG.H
@@ -26,7 +26,10 @@ Class
     Foam::XiGModels::instabilityG
 
 Description
-    Flame-surface instabilityG flame-wrinking generation rate coefficient model.
+    Flame-surface instabilityG flame-wrinking generation rate coefficient model
+    used in \link XiModel.H \endlink.
+
+    See Technical Report SH/RE/01R for details on the PDR modelling.
 
 SourceFiles
     instabilityG.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/XiModel/XiModel.H b/applications/solvers/combustion/PDRFoam/XiModels/XiModel/XiModel.H
index 93229e4de32753fd397c5f8d3cd2ab69375dc144..f44d1d5308aa13f83b94dc78634b6bc01740be4f 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/XiModel/XiModel.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/XiModel/XiModel.H
@@ -29,8 +29,10 @@ Description
     Base-class for all Xi models used by the b-Xi combustion model.
     See Technical Report SH/RE/01R for details on the PDR modelling.
 
-    Xi is given through an algebraic expression (algebraic.H),
-    by solving a transport equation (transport.H) or a fixed value (fixed.H).
+    Xi is given through an algebraic expression (\link algebraic.H \endlink),
+    by solving a transport equation (\link transport.H \endlink) or a
+    fixed value (\link fixed.H \endlink).
+
     See report TR/HGW/10 for details on the Weller two equations model.
 
     In the algebraic and transport methods \f$\Xi_{eq}\f$ is calculated in
@@ -45,6 +47,8 @@ Description
 
         \f$ \dwea{b} \f$ is the regress variable.
 
+        \f$ \Xi_{coeff} \f$ is a model constant.
+
         \f$ \Xi^* \f$ is the total equilibrium wrinkling combining the effects
         of the flame inestability and turbulence interaction and is given by
 
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/algebraic/algebraic.H b/applications/solvers/combustion/PDRFoam/XiModels/algebraic/algebraic.H
index 524bd582ec7b724fb5899c905cc8693c2fafc323..fdb2fc20b95bfb49cff519a86e6c76edd51fc3c2 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/algebraic/algebraic.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/algebraic/algebraic.H
@@ -28,6 +28,8 @@ Class
 Description
     Simple algebraic model for Xi based on Gulders correlation
     with a linear correction function to give a plausible profile for Xi.
+    See report TR/HGW/10 for details on the Weller two equations model.
+    See \link XiModel.H \endlink for more details on flame wrinkling modelling.
 
 SourceFiles
     algebraic.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/fixed/fixed.H b/applications/solvers/combustion/PDRFoam/XiModels/fixed/fixed.H
index 940c4b55faccb6fb9b3a583ff5d891ac2d20def5..968ed87d04e4962f9d3c539c684a9082e2a834a9 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/fixed/fixed.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/fixed/fixed.H
@@ -26,7 +26,8 @@ Class
     Foam::XiModels::fixed
 
 Description
-    Fixed value model for Xi.
+    Fixed value model for Xi. See \link XiModel.H \endlink for more details
+    on flame wrinkling modelling.
 
 SourceFiles
     fixed.C
diff --git a/applications/solvers/combustion/PDRFoam/XiModels/transport/transport.H b/applications/solvers/combustion/PDRFoam/XiModels/transport/transport.H
index d1e4e90cf1a7874f3602df677d2e11fb52945032..71db2b7e57ff2fb641fd85f63d36d186d6ae6b58 100644
--- a/applications/solvers/combustion/PDRFoam/XiModels/transport/transport.H
+++ b/applications/solvers/combustion/PDRFoam/XiModels/transport/transport.H
@@ -28,6 +28,8 @@ Class
 Description
     Simple transport model for Xi based on Gulders correlation
     with a linear correction function to give a plausible profile for Xi.
+    See report TR/HGW/10 for details on the Weller two equations model.
+    See \link XiModel.H \endlink for more details on flame wrinkling modelling.
 
 SourceFiles
     transport.C