Zhang Y, Liu Q. Cobalt(II) Sulfamate as An Efficient Catalyst for Synthesis of Bis(1H-Indol-3-yl)methanes. ajc [Internet]. 2012 Jun. 30 [cited 2024 Nov. 22];24(11):5302-4. Available from: https://asianpubs.org/index.php/ajchem/article/view/9841