edit install.md

install.md

@@ -40,4 +40,6 @@ To successfully compile, link and run VerHem application, few significant third
 * [METIS http page](http://glaros.dtc.umn.edu/gkhome/metis/metis/overview) 
 * [deal.ii](https://www.dealii.org/)  
 * [Trilinos](https://trilinos.github.io/) 
-* [MPI](https://en.wikipedia.org/wiki/Message_Passing_Interface): [openMPI](https://www.open-mpi.org/) or [mpich](https://www.mpich.org/) 
+* [MPI](https://en.wikipedia.org/wiki/Message_Passing_Interface): [openMPI](https://www.open-mpi.org/) or [mpich](https://www.mpich.org/) 
+
+For most of HPC cluster platforms, many of listed above are available by default. Frequently, users may notice that what they have to install manually are [deal.ii](https://www.dealii.org/) and [Trilinos](https://trilinos.github.io/), which both are cmake-configured libraries. On platform with [Spack](https://spack.io/), these dependencies will be more easy to handle. If user wish to run VerHem applications on their UNIX/Linux desktop or laptop, these dependencies may be installed from ports or package management systems.