Where to place the dll files to resolve the reference

Question

I have a dotnet project codebase without documentation. To build, there are batch files available. When I open the .sln file in VS, there are reference errors, which can be cleared by modifying .csproj file and updating

<Reference Include="MyLibrary.module, version=1.0.1, Culture=neutral, PublicKeyToken=randomstring" />

with

<Reference Include="MyLibrary.module, version=1.0.1, Culture=neutral, PublicKeyToken=randomstring">
<HintPath>path-to-dll-here</HintPath>
</Reference>

But rather then taking that path, I want to know, in which location, I can place necessary Referenced dll files such that those get resolved automatically.

I am getting MSB3245 warning and CS0246 errors.

Using VS 2013 on Win 10.