T. Sekhar, P. Thriveni, M. Harikrishna, and K. Murali, “One-Pot Synthesis of 3,4-Dihydropyrimidine-2(1H)-thione Derivatives Using DBU as Green and Recyclable Catalyst”, ajc, vol. 30, no. 6, pp. 1243–1246, Apr. 2018.