What is the correct magistal formula of trichloroacetic acid for the mention of genital wratjes?

One uses a 60 to 90% solution in water, of which a small quantity can be applied with an ear cleanser. This allows one to dry until a white fleece is formed. If an excess trichloroacetic acid was applied to uncontaminated tissue, the Pati ë NT should remove it with a liquid soap or NaHCO3 solution. The treatment is repeated weekly.