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README.md

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-# [OOMMF](https://math.nist.gov/oommf/) extension: Dzyaloshinskii-Moriya interaction (DMI) for crystallographic class C<sub>nv</sub>
+# [OOMMF](https://math.nist.gov/oommf/) extension: Dzyaloshinskii-Moriya interaction (DMI) for the crystallographic class C<sub>nv</sub>
 
 David Cortés-Ortuño<sup>1</sup>, Marijan Beg<sup>1,2</sup>, Vanessa Nehruji<sup>3</sup>, Ryan A. Pepper<sup>1</sup>, and Hans Fangohr<sup>1,2</sup>