Theorem of electromagnetic force surface representation in anisotropic region

The paper deals with the problem of surface-integral representation of an electromagnetic force in anisotropic region. The electromagnetic force calculated by means of Maxwell's and Lorentz's methods could lead to different results for some anisotropic media. The theorem of surface-integral representation of Lorentz's force in electromagnetic field is formulated. Examples of analytical calculations of forces for both the isotropic and anisotropic media in electromagnetic field are provided.