Raubenheimer, Helgard, and Hubert Schmidbaur. “Gold Coordination During Homogeneous Alkyne and Allene Cyclisation Catalysis: Coordination to Substrates, to Ancillary Ligands and in Intermediates”. South African Journal of Science, vol. 107, no. 3/4, Mar. 2011, p. 13 pages, https://sajs.co.za/article/view/10054.