diff --git a/doc/doxygen/README.md b/doc/doxygen/README.md
index 11b1a83d1be94a221736c21dec10b5b0a6ab817f..8eaa6f37da31bcfe32ce51486ad54fdba7007f47 100644
--- a/doc/doxygen/README.md
+++ b/doc/doxygen/README.md
@@ -60,3 +60,6 @@ If there are **function-arguments** that are not self-explanatory, they should b
 **Always explain all params or no params at all!** Otherwise Doxygen will throw an error.
 Template parameters are documented with `\tparam`.
 Additional Doxygen-commands that might be useful are `\note` for giving an important note/hint on what the function does as well as `\return` which specifies the return value (if applicable).
+
+April 2020 note: `\copydoc`,`\copybrief` and `\copydetails`, as well as `@copydoc`,`@copybrief` and `@copydetails` do not work with filenames in the current doxygen version.
+The bug is reported and has been fixed in doxygen pull request #7693. (It will work again in doxygen 1_8_18, probably at the end of 2020.)
diff --git a/doc/doxygen/modules.txt b/doc/doxygen/modules.txt
index 13cde77a349278477248a6c9eb00428fd98661d9..5f3a6f54eff887a56c6599f5a02f20414a736d18 100644
--- a/doc/doxygen/modules.txt
+++ b/doc/doxygen/modules.txt
@@ -14,7 +14,7 @@
      * \ingroup PorousmediumflowModels
      * \defgroup OnePModel 1p
      * \brief Single-phase (immiscible) Darcy flow
-     * \copydetails ./porousmediumflow/1p/model.hh
+     * For a detailed model decription see porousmediumflow/1p/model.hh
      */
         /*!
          * \ingroup OnePModel
@@ -31,19 +31,19 @@
      * \ingroup PorousmediumflowModels
      * \defgroup OnePNCModel 1pnc
      * \brief Single-phase, multi-component Darcy flow
-     * \copydetails ./porousmediumflow/1pnc/model.hh
+     * For a detailed model decription see porousmediumflow/1pnc/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup OnePNCMinModel 1pncmin
      * \brief Single-phase, multi-component Darcy flow with mineralization
-     * \copydetails ./porousmediumflow/1pncmin/model.hh
+     * For a detailed model decription see porousmediumflow/1pncmin/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup TwoPModel 2p
      * \brief Two-phase (immiscible) Darcy flow
-     * \copydetails ./porousmediumflow/2p/model.hh
+     * For a detailed model decription see porousmediumflow/2p/model.hh
      */
         /*!
          * \ingroup TwoPModel
@@ -60,13 +60,13 @@
      * \ingroup PorousmediumflowModels
      * \defgroup TwoPOneCModel 2p1c
      * \brief Two-phase, one-component Darcy flow
-     * \copydetails ./porousmediumflow/2p1c/model.hh
+     * For a detailed model decription see porousmediumflow/2p1c/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup TwoPTwoCModel 2p2c
      * \brief Two-phase, two-component Darcy flow
-     * \copydetails ./porousmediumflow/2p2c/model.hh
+     * For a detailed model decription see porousmediumflow/2p2c/model.hh
      */
         /*!
          * \ingroup TwoPTwoCModel
@@ -83,100 +83,100 @@
      * \ingroup PorousmediumflowModels
      * \defgroup TwoPNCModel 2pnc
      * \brief two-phase, multi-component Darcy flow
-     * \copydetails ./porousmediumflow/2pnc/model.hh
+     * For a detailed model decription see porousmediumflow/2pnc/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup TwoPNCMinModel 2pncmin
      * \brief Two-phase, multi-component Darcy flow with mineralization
-     * \copydetails ./porousmediumflow/2pncmin/model.hh
+     * For a detailed model decription see porousmediumflow/2pncmin/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup ThreePModel 3p
      * \brief Three-phase (immiscible) Darcy flow
-     * \copydetails ./porousmediumflow/3p/model.hh
+     * For a detailed model decription see porousmediumflow/3p/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup ThreePThreeCModel 3p3c
      * \brief Three-phase, three-component Darcy flow
-     * \copydetails ./porousmediumflow/3p3c/model.hh
+     * For a detailed model decription see porousmediumflow/3p3c/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup ThreePWaterOilModel 3pwateroil
      * \brief Three-phase, two-component Darcy flow with water (liquid & gas) and oil
-     * \copydetails ./porousmediumflow/3pwateroil/model.hh
+     * For a detailed model decription see porousmediumflow/3pwateroil/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup BoxDFMModel boxdfm
      * \brief Vertex-centered, continuous-pressure, conforming lower-dimensional discrete-fracture model
-     * \copydetails ./porousmediumflow/boxdfm/model.hh
+     * For a detailed model decription see porousmediumflow/boxdfm/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup CO2Model CO2
      * \brief Two-phase, two-component Darcy flow specialized for supercritical CO<sub>2</sub> storage
-     * \copydetails ./porousmediumflow/co2/model.hh
+     * For a detailed model decription see porousmediumflow/co2/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup MineralizationModel mineralization
      * \brief Model adding components that can precipitate as a solid phase to a standard Darcy flow model
      *
-     * \copydetails ./porousmediumflow/mineralization/model.hh
+     * For a detailed model decription see porousmediumflow/mineralization/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup MPNCModel mpnc
      * \brief Generalized multi-phase, multi-component Darcy flow
      *
-     * \copydetails ./porousmediumflow/mpnc/model.hh
+     * For a detailed model decription see porousmediumflow/mpnc/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup NonEquilibriumModel NonEquilibrium
      * \brief Model that adds nonequilibrium equations to another porous medium flow model (only used in MPNCModel currently)
-     * \copydetails ./porousmediumflow/nonequilibrium/model.hh
+     * For a detailed model decription see porousmediumflow/nonequilibrium/model.hh
      */
         /*!
          * \ingroup NonEquilibriumModel
          * \defgroup ThermalNonEquilibriumModel ThermalNonEquilibrium
          * \brief Model that adapts the energy localresidual to thermal nonequilibrium
-         * \copydetails ./porousmediumflow/nonequilibrium/thermal/localresidual.hh
+         * For a detailed model decription see porousmediumflow/nonequilibrium/thermal/localresidual.hh
          */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup NIModel nonisothermal
      * \brief Model that adds an energy equation (thermal equilibrium) to another porous medium flow model
      *
-     * \copydetails ./porousmediumflow/nonisothermal/model.hh
+     * For a detailed model decription see porousmediumflow/nonisothermal/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup RichardsModel Richards
      * \brief Richards flow
-     * \copydetails ./porousmediumflow/richards/model.hh
+     * For a detailed model decription see porousmediumflow/richards/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup RichardsNCModel Richards nc
      * \brief Richards multi-component flow
-     * \copydetails ./porousmediumflow/richardsnc/model.hh
+     * For a detailed model decription see porousmediumflow/richardsnc/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup SolidEnergyModel Solid energy
      * \brief Energy equation for the solid (general heat equation)
-     * \copydetails ./porousmediumflow/solidenergy/model.hh
+     * For a detailed model decription see porousmediumflow/solidenergy/model.hh
      */
     /*!
      * \ingroup PorousmediumflowModels
      * \defgroup TracerModel Tracer
      * \brief Multi-component advection-diffusion-reaction model with given velocity field
-     * \copydetails ./porousmediumflow/tracer/model.hh
+     * For a detailed model decription see porousmediumflow/tracer/model.hh
      */
 
 /* ***************** FreeflowModels ******************/
@@ -188,25 +188,25 @@
      * \ingroup FreeflowModels
      * \defgroup NavierStokesModel Navier-Stokes
      * \brief Single-phase Navier-Stokes flow
-     * \copydetails ./freeflow/navierstokes/model.hh
+     * For a detailed model decription see freeflow/navierstokes/model.hh
      */
     /*!
      * \ingroup FreeflowModels
      * \defgroup RANSModel Reynolds-Averaged Navier-Stokes
      * \brief Single-phase Reynolds-Averaged Navier-Stokes flow
-     * \copydetails ./freeflow/rans/model.hh
+     * For a detailed model decription see freeflow/rans/model.hh
      */
         /*!
          * \ingroup RANSModel
          * \defgroup ZeroEqModel 0-Eq. Models
          * \brief Zero-equation or algebraic turbulence models
-         * \copydetails ./freeflow/rans/zeroeq/model.hh
+         * For a detailed model decription see freeflow/rans/zeroeq/model.hh
          */
         /*!
          * \ingroup RANSModel
          * \defgroup OneEqModel 1-Eq. Models
          * \brief One-equation turbulence model by Spalart-Allmaras
-         * \copydetails ./freeflow/rans/oneeq/model.hh
+         * For a detailed model decription see freeflow/rans/oneeq/model.hh
          */
         /*!
          * \ingroup RANSModel
@@ -217,37 +217,37 @@
          * \ingroup TwoEqModel
          * \defgroup KEpsilonModel K-epsilon model
          * \brief K-epsilon model
-         * \copydetails ./freeflow/rans/twoeq/kepsilon/model.hh
+         * For a detailed model decription see freeflow/rans/twoeq/kepsilon/model.hh
          */
         /*!
          * \ingroup TwoEqModel
          * \defgroup KOmegaModel K-omega model
          * \brief K-omega model
-         * \copydetails ./freeflow/rans/twoeq/komega/model.hh
+         * For a detailed model decription see freeflow/rans/twoeq/komega/model.hh
          */
         /*!
          * \ingroup TwoEqModel
          * \defgroup LowReKEpsilonModel Low-Re k-epsilon model
          * \brief Low-Re k-epsilon model
-         * \copydetails ./freeflow/rans/twoeq/lowrekepsilon/model.hh
+         * For a detailed model decription see freeflow/rans/twoeq/lowrekepsilon/model.hh
          */
     /*!
      * \ingroup FreeflowModels
      * \defgroup FreeflowNCModel Compositional
      * \brief Single-phase multi-component free-flow flow models
-     * \copydetails ./freeflow/compositional/navierstokesncmodel.hh
+     * For a detailed model decription see freeflow/compositional/navierstokesncmodel.hh
      */
     /*!
      * \ingroup FreeflowModels
      * \defgroup FreeflowNIModel Nonisothermal
      * \brief An energy equation adaptor for isothermal free-flow models
-     * \copydetails ./freeflow/nonisothermal/model.hh
+     * For a detailed model decription see freeflow/nonisothermal/model.hh
      */
     /*!
      * \ingroup FreeflowModels
      * \defgroup ShallowWaterModel 2D shallow water model
      * \brief Two-dimensional shallow water flow (depth-averaged)
-     * \copydetails ./freeflow/shallowwater/model.hh
+     * For a detailed model decription see freeflow/shallowwater/model.hh
      */
 /*!
  * \defgroup Geomechanics Geomechanics Models
@@ -257,13 +257,13 @@
      * \ingroup Geomechanics
      * \defgroup Elastic Solid mechanics w/o fluid pressure
      * \brief Models linear elastic deformation of a solid. Disregards fluid pressure.
-     * \copydetails ./geomechanics/elastic/model.hh
+     * For a detailed model decription see geomechanics/elastic/model.hh
      */
     /*!
      * \ingroup Geomechanics
      * \defgroup PoroElastic Solid mechanics with fluid pressure
      * \brief Models linear elastic deformation of a solid. Takes fluid pressure into account.
-     * \copydetails ./geomechanics/poroelastic/model.hh
+     * For a detailed model decription see geomechanics/poroelastic/model.hh
      */
 
 /* ***************** Benchmarks and Tests ******************/
diff --git a/dumux/freeflow/compositional/kepsilonncmodel.hh b/dumux/freeflow/compositional/kepsilonncmodel.hh
index f0f4b971fa9da6a5a8756f7a51892458eb003791..b66f570c888c4df2fda36b12df689aedf02f1ac6 100644
--- a/dumux/freeflow/compositional/kepsilonncmodel.hh
+++ b/dumux/freeflow/compositional/kepsilonncmodel.hh
@@ -22,7 +22,7 @@
  *
  * \brief A single-phase, multi-component k-epsilon model
  *
- * \copydoc dumux/freeflow/compositional/navierstokesncmodel.hh
+ * For a detailed model decription see dumux/freeflow/compositional/navierstokesncmodel.hh
  */
 
 #ifndef DUMUX_KEPSILON_NC_MODEL_HH
diff --git a/dumux/freeflow/compositional/komegancmodel.hh b/dumux/freeflow/compositional/komegancmodel.hh
index 1a4c22f8fd841c4f8bc115a6aa3cfa15c1026739..0aa09c71ae97ef479166d7a480c2f5065c3b2472 100644
--- a/dumux/freeflow/compositional/komegancmodel.hh
+++ b/dumux/freeflow/compositional/komegancmodel.hh
@@ -22,7 +22,7 @@
  *
  * \brief A single-phase, multi-component k-omega model
  *
- * \copydoc dumux/freeflow/compositional/navierstokesncmodel.hh
+ * For a detailed model decription see dumux/freeflow/compositional/navierstokesncmodel.hh
  */
 
 #ifndef DUMUX_KOMEGA_NC_MODEL_HH
diff --git a/dumux/freeflow/compositional/lowrekepsilonncmodel.hh b/dumux/freeflow/compositional/lowrekepsilonncmodel.hh
index 3b5059b804f4ca24b4446ee3f59b7d720e204d8f..1c78eb69a8bed995b82097784a827d5b31efcc31 100644
--- a/dumux/freeflow/compositional/lowrekepsilonncmodel.hh
+++ b/dumux/freeflow/compositional/lowrekepsilonncmodel.hh
@@ -22,7 +22,7 @@
  *
  * \brief A single-phase, multi-component low-Re k-epsilon model
  *
- * \copydoc dumux/freeflow/compositional/navierstokesncmodel.hh
+ * For a detailed model decription see dumux/freeflow/compositional/navierstokesncmodel.hh
  */
 
 #ifndef DUMUX_LOWREKEPSILON_NC_MODEL_HH
diff --git a/dumux/freeflow/compositional/navierstokesncmodel.hh b/dumux/freeflow/compositional/navierstokesncmodel.hh
index 8879363a582becce135d54d7f38d345faced67de..63a26feb04ed2fd87132fd8269988008c393cf50 100644
--- a/dumux/freeflow/compositional/navierstokesncmodel.hh
+++ b/dumux/freeflow/compositional/navierstokesncmodel.hh
@@ -20,9 +20,11 @@
  * \file
  * \ingroup FreeflowNCModel
  *
- * \copydoc dumux/freeflow/navierstokes/model.hh
+ * \brief A single-phase, multi-component free-flow model
  *
- * The system is closed by a <B> component mass/mole balance equation </B> for each component \f$\kappa\f$:
+ * For an equations not specific to multiple components see dumux/freeflow/navierstokes/model.hh
+ *
+ * The multi-component system is closed by a <B> component mass/mole balance equation </B> for each component \f$\kappa\f$:
  * \f[
  *    \frac{\partial \left(\varrho X^\kappa\right)}{\partial t}
  *    + \nabla \cdot \left( \varrho {\boldsymbol{v}} X^\kappa
diff --git a/dumux/freeflow/compositional/oneeqncmodel.hh b/dumux/freeflow/compositional/oneeqncmodel.hh
index 411124141a542aff9ffa4b88728375f33fa7e49a..01a96fcb406b2172c7010fe4da674bb803f343e8 100644
--- a/dumux/freeflow/compositional/oneeqncmodel.hh
+++ b/dumux/freeflow/compositional/oneeqncmodel.hh
@@ -22,7 +22,7 @@
  *
  * \brief A single-phase, multi-component one-equation model
  *
- * \copydoc dumux/freeflow/compositional/navierstokesncmodel.hh
+ * For a detailed model decription see dumux/freeflow/compositional/navierstokesncmodel.hh
  */
 
 #ifndef DUMUX_ONEEQ_NC_MODEL_HH
diff --git a/dumux/freeflow/compositional/zeroeqncmodel.hh b/dumux/freeflow/compositional/zeroeqncmodel.hh
index 498f00ec596c1d7aeb51b987ba4c13fdc7158f7f..da41a68fd9852a20eefb43958986ef3744484f93 100644
--- a/dumux/freeflow/compositional/zeroeqncmodel.hh
+++ b/dumux/freeflow/compositional/zeroeqncmodel.hh
@@ -22,7 +22,7 @@
  *
  * \brief A single-phase, multi-component Reynolds-Averaged Navier-Stokes 0-Eq. model
  *
- * \copydoc dumux/freeflow/compositional/navierstokesncmodel.hh
+ * For a detailed model decription see dumux/freeflow/compositional/navierstokesncmodel.hh
  */
 
 #ifndef DUMUX_ZEROEQ_NC_MODEL_HH