RATIONAL DESIGN OF AN EFFICIENT ONE-POT SYNTHESIS OF 6H-PYRROLO[2,3,4-GH]PERIMIDINES IN POLYPHOSPHORIC ACID Статья Aksenov A.V., Aksenov N.A., Ovcharov D.S., Aksenov D.A., Griaznov G., Voskressensky L.G., Rubin M. RSC Advances. Том vol 6. 2016.