Subgroups of minimal non-abelian 2-groups I want to determine all maximal subgroups of the following type of minimal non-abelian 2-group: $\langle a, b, c : a^{2^{s}} = b^2 = c^{2} = 1, [a,c] = [b,c] = 1, [a, b]=c\rangle$ of order $2^{s+2}$; $s \ge 1$. 
Every hint will be appreciate. Many thanks.

You can calculate the  commutator subgroup $[G,G]$ (it seems not difficult). Since  all maximal subgroups of $G$ include $[G,G]$, there is a bijection between them and maximal subgroups  of $G/[G,G]$.
