1. Cooper MA, Holden CM, Loftus P, Whittaker D. 1973. J. Chem. Soc. Perkin Trans. II 665.
2. Garnero J. 1976. Rivista Italiana EPPOS 58: 105.
3. Granger R, Passet J, Lamy J. 1975. Rivista Italiana EPPOS 57: 446.
4. Norin T, Smedman L-A. 1971. Acta Chem. Scand. 25: 2010.
5. Tolstikov GA, Lishtvanova LN, Goryaev MI. 1963. Zh. Obshch. Khim. 33: 683.