Update README.md

Author: dsambit

README.md

@@ -12,7 +12,7 @@ Installation instructions
 -------------------------
 
 DFT-FE code builds on top of the deal.II library for everything that has to do with finite elements, geometries, meshes, etc., and, through deal.II on p4est for parallel adaptive mesh handling.
-The steps to install the necessary dependencies and DFT-FE itself are described in the *Installation* section of the DFT-FE manual (download the release version manual [here](https://github.com/dftfeDevelopers/dftfe/blob/manual/manual-release.pdf)). 
+The steps to install the necessary dependencies and DFT-FE itself are described in the *Installation* section of the DFT-FE manual (download the release version manual [here](https://github.com/dftfeDevelopers/dftfe/blob/manual/manual-release1.2.pdf)). 
 
 We have created several shell based installation scripts for the current release version of DFT-FE (`release(*)` branch) on various machines:
   - [OLCF Frontier](https://github.com/dftfeDevelopers/install_DFTFE/tree/frontierRelease)