Using Dependencies from another multi project build

I am working on a project where I have a java library project that needs to reference another java project that happens to be a multi project build. I want to reference the multi-project as a project reference and the only way I know to do this is to add a settings.gradle file to my java libraryproject.
When I do this I get the error Could not find method compile() for arguments [org.eclipse.xtext:org.eclipse.xtext.ecore:2.12.0]

Project A is a multi-project build with a parent project and subprojects
Project B is a java library project

I need to reference project A in project B