Add references for abstract parser.
Add references for abstract parser.

melentyev/YaccConstructor,sanyaade-g2g-repos/YaccConstructor,Albiglittle/YaccConstructor,RomanBelkov/YaccConstructor,nbIxMaN/YaccConstructor,RomanBelkov/YaccConstructor,fedorovr/YaccConstructor,YaccConstructor/YaccConstructor,Albiglittle/YaccConstructor,Albiglittle/YaccConstructor,melentyev/YaccConstructor,YaccConstructor/YaccConstructor,sanyaade-g2g-repos/YaccConstructor,melentyev/YaccConstructor,YaccConstructor/YaccConstructor,fedorovr/YaccConstructor,RomanBelkov/YaccConstructor,VereshchaginaE/YaccConstructor,VereshchaginaE/YaccConstructor,nbIxMaN/YaccConstructor,sanyaade-g2g-repos/YaccConstructor,VereshchaginaE/YaccConstructor,fedorovr/YaccConstructor,nbIxMaN/YaccConstructor