Fibre bundle which is not an open map
55484
Proving that the map from a topological space to a fiber bundle is open.
70218
Flat not projective, projective not free
55263
Path connected space that is not locally connected
143043
When is a local homeomorphism a covering map?
154009
Closed, simply connected manifolds which are not spheres
4717
The union of linear subspaces is not necessarily a subspace
57653
Relation between line bundles over $\mathbb{P}^1$ in geometry and topology
81220
Space which is connected but not path-connected
12772
A fiber bundle over Euclidean space is trivial.
80524
Path-connected and locally connected space that is not locally path-connected
143254
Closed ball not a manifold.
2348
Show that the sphere, S, and $\mathbb{R}^2$ is not homeomorphic
106736
Poincaré maps and interpretation
63442
Show that if $U$ is an open connected subspace of $\mathbb{R}^2$, then $U$ is path connected
78085
A non orientable closed surface cannot be embedded into $\mathbb{R}^3$
52629
Example 1, Sec. 22 in Munkres' TOPOLOGY, 2nd edition: How to verify that this map is closed?
124713
Projective space is not affine