https://download.eclipse.org/modeling/mdt/ocl/javadoc/5.0.0/org/eclipse/ocl/examples/xtext/essentialocl/services/EssentialOCLValueConverterService.DoubleQuotedStringConverter.html
EssentialOCLValueConverterService.DoubleQuotedStringConverter (MDT-OCL Documentation)
mdtocldocumentation