Ágai, Béla, Gyula Hornyák, and Károly Lempert. 1974. “PYRIMIDINES AND CONDENSED DERIVATIVES, III* THE SYNTHESIS OF SOME ISOCYTOSINES AND RELATED IMIDAZO[1,2-A]- AND -[1,2-C ]PYRIMIDINONES ”. Periodica Polytechnica Chemical Engineering 18 (1):47-72.