1. R. B. Woodward, M. P. Cava, W. D. Ollis, A. Hunger, H. U. Dacniker and K. Schenker, The Total Synthesis of Strychnine, Tetrahedron, 1963, 19, 247-288 pertinent p.248.
2. Stephan Berger and Dieter Sicker, Classics in Spectroscopy, Wiley-VCH, 2009, pertinent p.105.
3. P. J. Pelletier and J. B. Caventou, Note sur un novel alcali, Annales de Chimie et de Physique
1818, 323-336.
4. Sir Arthur Conan Doyle, Collections (Adventures of Sherlock Holmes), Sign of Four, Vol. 1, Bentham Classics, 2003, 121-236, pertinent page, 162, originally published in 1890.
5. G. F. Smith, in The Alkaloids, Ed. RFH Manske, Academic Press, New York, 1965, Vol 8, pp.591-671.