Multiple System.* not resolved issue

[naveen7v]

Building on Ubuntu 16.04... Everything is good except that Rebuld.sh ends with

Cleaning up CARLA Plugin...
Cleaning up CARLAUE4...
Generate Unreal project files...

Setting up Unreal Engine 4 project files...

+ xbuild Source/Programs/UnrealBuildTool/UnrealBuildTool.csproj /verbosity:quiet /nologo /p:TargetFrameworkVersion=v4.0 /p:Configuration=Development
/usr/lib/mono/4.5/Microsoft.Common.targets:  warning : Reference 'System.Xml.Linq' not resolved
/usr/lib/mono/4.5/Microsoft.Common.targets:  warning : Reference 'System.Data.DataSetExtensions' not resolved
/usr/lib/mono/4.5/Microsoft.Common.targets:  warning : Reference 'Microsoft.CSharp' not resolved
/usr/lib/mono/4.5/Microsoft.Common.targets:  warning : Reference 'System.Data' not resolved

Build CarlaUE4 project...

make: *** No rule to make target 'CarlaUE4Editor'.  Stop.

follwed issue 103 but it seems different for mycase

Any help/pointers please

Thank you

[naveen7v]

sorry...should have read the unreal documentation first...
mono install and mcs install solved it