A generalization of L{\"u}roth's theorem expresses that every transcendence degree 1 subfield of the rational function field is a simple extension. In this note we show that a classical proof of this theorem also holds to prove this generalization.

翻译：L~“u}roth”理论的概括性表示,理性功能字段的每个超度度度1子字段都是一个简单的扩展。在本说明中,我们表明,典型的理论证明也证明这种概括性。