The Elastic Field Caused by a Circular Cylindrical Inclusion—Part I: Inside the Region x[sub 1][sup 2] + x[sub 2][sup 2] < a[sup 2], −∞ < x[sub 3] < ∞ Where the Circular Cylindrical Inclusion is Expressed by x[sub 1][sup 2] + x[sub 2][sup 2] ≤ a[sup 2], −h ≤ x[sub 3] ≤ h