1. H. Mayer and O. Isler, in Carotenoids (ed. O. Isler ), p. 325, Birkhäuser, Basel (1971).
2. L. Bradsma, Preparative Acetylene Chemistry, 2nd ed., Elsevier, New York (1988).
3. P. S. Manchand, R. Rüegg, U. Schwieter, P. T. Siddons and B. C. L. Weedon, J. Chem. Soc., 2019 (1965).
4. B. J. Wakefield, Organolithium Methods, Academic Press, New York (1988).
5. L. Skatteböl, E. R. H. Jones and M. C. Whiting, Org. Synth., Coll. Vol. IV, 792 (1963).