The following theorem is usually attributed to [Eduard Study](https://en.wikipedia.org/wiki/Eduard_Study): > Let $f(x,y)$ and $g(x,y)$ be polynomials in two variables over a field, with $f$ irreducible. If $f\nmid g$ then the curves $C_f:f=0$ and $C_g:g=0$ have finitely many points of intersection. Consequently, If the field is algebraically closed and $C_f\subseteq C_g$ (hence $C_f\cap C_g$ has infinitely many points) then $f|g$. However, I have not been able to track down any reference to this result outside of modern textbooks. Questions: - What is the original reference for this result? - What did Study actually prove? - What was the context? (I presume that Study was looking at invariant theory of ternary forms.) - Did this result directly influence later versions of the Nullstellensatz? Thanks.