in [@JD 37–38], whereas Bertini described it as well known, part of the folklore of the era. He republished his paper [@Bertini1891] three years later in [*Mathematische Annalen*]{}, after noticing that prominent French authors – among them Picard, Simart, and Poincaré – continued to mention the theorem without citing his proof. On the other hand, Bertini failed to reference [@Noether1871] and other subsequent papers that showed how to transform a curve to obtain another with simple multiple points, i.e. distinct tangents for each branch. This oversight was perhaps entirely innocent, but in fact Noether’s work represented the most difficult part in proving Clebsch’s Theorem. As we shall see, this aspect helps to explain Noether’s evident irritation in some of his letters to Klein.

Klein’s Correspondence with Noether
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When Felix Klein received Bertini’s note in early January 1894, what he read immediately set off alarm bells. So he turned to his long-time friend, Max Noether, asking him to help put out a potential fire.[^4] Klein quickly realized that Bertini’s proof of this folklore theorem in birational geometry was essentially the same as one he had learned about from Clebsch some 25 years earlier. He also vaguely remembered writing to Noether 