Bhuiyan, M. M. H., K. M. M. Rahman, M. K. Hossain, and M. Fakruddin. “FUSED PYRIMIDINES: PART-I: SYNTHESIS OF IMIDAZO[1,2-a]THIENO[2,3-D]- PYRIMIDIN-5(1H)- IMINE AND PYRIMIDO[1,2-A] THIENO[2,3-D] PYRIMIDIN-6-IMINE”. Biological Sciences - PJSIR, vol. 47, no. 4, Aug. 2004, pp. 256-8, https://v2.pjsir.org/index.php/biological-sciences/article/view/1530.