Yes it should really be apple vinegar. I have found books on amazon. Just search for apple vinegar.
I forgot to tell also... you can use it also directly on your spots. Clean your face first. I always used to clean my face with something, because I hade very greasy skin, but now I clean it only with water. Make sure that your hands are clean, pour some vinegar in your hands, apply it on your face and DON'T WASH IT OFF !!! It burns a little bit, but has a great effect. A friend of mine has problems of dry skin in the winter, because of the dry air caused by the heating. He always gets a very red, dry skin in his face. No moisturizer helps. Apple vingar works for him within two days.
To be clear, I am meant to put the vinegar onto the area of my skin which has spots on it, not my face right? My face is spot-free, it's just my back that is infected, so I should put the vinegar on my back right? I don't use any other products on my skin, just some kind of shower gel or shampoo, no specific skin products and chemicals etc. I'll try to get my hands on apple vinegar, I have had it before when I was little.