Agnihotri, R., Agnihotri, N., Kamal, R., & R. Mehta, J. (2010). 3-Hydroxy-2-(3´-methyl-2´-thienyl)-4-oxo-4H-1-benzopyran as an Analytical Reagent for the Spectrophotometric Determination of Tungsten(VI). Asian Journal of Chemistry, 20(6), 4469–4476. Retrieved from https://asianpubs.org/index.php/ajchem/article/view/19046