Assertion: virus's shape | /r/HasProperty | a 20-sided polygon
Facets:
Source sentences:
text: The sphere shape is actually a 20-sided polygon (icosahedron).
text: Some viruses are rod-shaped, others are icosahedral (a roughly spherical shape that is actually a 20-sided polygon), and still others have complex shapes consisting of a multisided "head" and a cylindrical "tail.