Impossibility of cloning of quantum coherence

It is well known that it impossible to clone an arbitrary quantum state. However, this inability does not lead directly no-cloning of coherence. Here, we show the coherence state which a stronger statement than 'no-cloning state'. In particular, with ancillary system as machine state, states whose greater on transformations are defined. Also, characterize class for cloning will be possible given choice machine. Furthermore, find maximum range can cloned perfectly. The impossibility proof also holds when do include states.