Isomorphic normal subgroups
2254
Finite group with isomorphic normal subgroups and non-isomorphic quotients?
78580
Is $SL_n(\mathbb{R})$ a normal subgroup in $GL_n(\mathbb{R})$?
125244
Equivalent definitions of normal subgroups
109236
Subgroups containing kernel of group morphism to an abelian group are normal.
128300
Prove that a group with exactly two proper nontrivial subgroups is isomorphic to $\mathbb{Z}_{pq}$ or $\mathbb{Z}_{p^3}$.
103423
Normal subgroup where G has order prime
75568
Subgroup of index $2$ is Normal
123610
How to show that the commutator subgroup is a normal subgroup
57227
Maximal normal $\pi$-subgroups and torsion subgroups
30236
isomorphic groups related in direct product.
13523
Are normal subgroups transitive?
61373
A normal subgroup that is not a characteristic
23579
If $G$ is isomorphic to $H$, then ${\rm Aut}(G)$ is isomorphic to ${\rm Aut}(H)$
30793
Intuition behind normal subgroups
151862
Is any subgroup of a direct product isomorphic to a direct product of subgroups?
146028
$GL(n, \mathbb{C})$ is isomorphic to a subgroup of $GL(2n, \mathbb{R})$
14255
Commutator subgroup and cyclic normal subgroup