If you are looking for an effective dog barking stopper, then you should consider a citronella anti-bark spray collar. As demonstrated by this individual, all that is needed to attach the spray collar around the neck of the barking dog.  Once the dog begins to bark, the collar will recognize this and spray a citronella based mix into the nose of the dog. This is non-toxic and not harfmul  to the dogs. Dogs do not like the smell of the citronella and they will quickly realize that everytime that they bark, they will be sprayed.

This is very effective as demonstrated by the young man above. He gets blased by the citronella spray and if it works on him, then this is a really good dog barking stopper.