# Double Pointed Fortissimo Space is Lindelöf

From ProofWiki

## Theorem

Let $T = \left({S, \tau}\right)$ be a Fortissimo space.

Let $T \times D$ be the double pointed topology on $T$.

Then $T \times D$ is a Lindelöf space.

## Proof

## Sources

- Lynn Arthur Steen and J. Arthur Seebach, Jr.:
*Counterexamples in Topology*(1970)... (previous)... (next): $\text{II}: \ 25: \ 4$