Unmixed local rings with minimal Hilbert-Kunz multiplicity are regular

Unmixed local rings with minimal Hilbert-Kunz multiplicity are regular
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by Craig Huneke and Yongwei Yao PDF

Proc. Amer. Math. Soc. 130 (2002), 661-665 Request permission

We give a new and simple proof that unmixed local rings having Hilbert-Kunz multiplicity equal to $1$ must be regular.

References

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