[1]
N. Tavakoli-Hoseini and A. Davoodnia, “Silica Gel-Supported Polyphosphoric Acid: A Mild, Efficient and Reusable Catalyst for the One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles”, ajc, vol. 22, no. 9, pp. 7197–7200, Jul. 2010.