1. Solvent extraction of gold and platinum-group metals using 2-nonylpyridine 1-oxide, and the crystal and molecular structure of bis(2-nonylpyridine 1-oxide)hydrogen(1 +) tetrachloroaurate(III) Michael G. B. Drew,Lyn R. Glaves,Michael J. Hudson J. Chem. Soc. Dalton Trans. 1985 771