G&T / Gramophone Monarch poster - original or repro ?

[Calle]

I saw this G&T / Gramophone Monarch poster and was wondering if it's an original or a reproduction ?

[soundgen]

impossible top tell unless you take it out of the frame and look at the back , as it will be from a magazine newspaper such as the London Illustrated news it will have printing on the back , no printing would mean a copy

[Odeon]

A repro, in my opinion.
No one, back then, would have framed a advertising. Why? But, unframed it would´t survived in that condition. Even if it had been framed for a display window or something else, the paper looks to "perfect". Just my two cent...