[Math] Hopfian and Co-Hopfian groups (examples)

Question

Hi,
I'm looking for examples of groups that are both Hopfian and Co-Hopfian. I have a non trivial (and beautiful, at least to me) example: $\mathrm{SL}(n,\mathbb{Z})$ (with $n>2$).

Do you know others (non trivial)?

Thank you.

Answer 1

Mapping class groups of closed surfaces are both Hopfian and co-Hopfian (the former follows from residual finiteness, and the latter is due to Ivanov-McCarthy).

Out(F_n) also has both properties (residual finiteness and a theorem of Farb-Handel).