12 Pentominoes

Theorem
There exist $12$ distinct pentominoes, up to reflection and rotation in the plane:


 * 12Pentominoes.png

Proof
Note, that all of them except one can be Definition:folded into cube without one side.

Let's name the candidates by english keys: d(b,p)&n"u)t|f,<_>+? Work to be done yet to establish method of creation...