@book{11766, author = {Huggett, S. A. and Tod, K. P.}, title = {An introduction to twistor theory /}, publisher = {Cambridge University Press,}, year = {1985.}, address = {Cambridge [Cambridgeshire] ;}, note = {Includes index.}, url = {http://www.loc.gov/catdir/description/cam031/85017499.html} }