I just recently removed about four layers of wallpaper from a plaster wall using wallpaper remover. This comes in a liquid concentrate that you mix with water and then spray on the wallpaper with a spray bottle. However, if your paper has been painted over or if it has a washable surface,you will need to use a "paper tiger". This tool(I paid about $5 for one) has litle wheels with sharp teeth that score the paper so the remover can get into the backing. your local hardware or home improvement store should have both this items. Good Luck!