Published online by Cambridge University Press: 24 October 2008
1. Let P = 0, Q = 0, U = 0, V = 0 represent four independent quadric surfaces, and consider the equation
* Severi, , Atti Torino, 39 (1904), 503.Google Scholar
† Enriques, , Lezioni sulla teoria delle superficie algebriche (Padova, 1932), p. 341.Google Scholar
‡ I am indebted to Mr E. A. Maxwell for correcting my original proof. See also § 3.
* Enriques, loc. cit. p. 206.
† Enriques, , Rendiconti Bologna (2), 11 (1907), 11–15.Google Scholar
‡ This was first remarked by Professor Baker.