# On rational surfaces, II

@inproceedings{Nagata1960OnRS, title={On rational surfaces, II}, author={Masayoshi Nagata}, year={1960} }

In § 1 of the present paper, we introduce the notion of a virtual linear system on a non-singular projective surface and we clarify the theories o f infinitely near points, of divisors and o f linear system with preassigned base conditions. We introduce in § 2 the notions of a numerical types and of non-special points with respect to Cremona transformations. They play important roles in § 3 in order to prove characterizations and existence theorems o f exceptional curves of the first kind and…

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