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(*  Reflected boolean property and morphic image, injection, bijection *)
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Section MorphicImage.
Variables aT rT : finGroupType.
Variables (D : {group aT}) (f : {morphism D >-> rT}) (x : aT).
Hypothesis Dx : x \in D.

Lemma sub_cyclic_char G H : cyclic G -> (H \char G) = (H \subset G).