File:The National Shotgun 1978 film poster.jpg

Summary
The image linked here is claimed to be used under fair use as:

It is a low-resolution copy of a film poster, Its use here does not limit the copyright owner's ability to market the film in any way, It is being used for informational purposes only, not for profit,

Specifically,

In La escopeta nacional, it is the best possible way to illustrate the subject.