Fig. 1From: The Green tensor of Mindlin’s anisotropic first strain gradient elasticityThe unit sphere in Fourier space. The unit vector κ(θ,ϕ) is defined by the azimuth angle ϕ, and the zenith angle θ measured from the axis \(\hat {\boldsymbol {e}}_{3}=\boldsymbol {x}/x\)Back to article page