A nonsimply connected 3-manifold, also called a dodecahedral space.
Poincaré Manifold
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References
Rolfsen, D. Knots and Links. Wilmington, DE: Publish or Perish Press, pp. 245, 290, and 308, 1976.Referenced on Wolfram|Alpha
Poincaré ManifoldCite this as:
Weisstein, Eric W. "Poincaré Manifold." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/PoincareManifold.html