A method 13 wherein the aqueous acid solution contains about 0.01% to about 1.0% by weight of the surfactant based on {HEAD ~ the amount} of {TAIL ~ acid} 
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A method 13 wherein the aqueous acid solution contains about 0.01 % to about 1.0 % by weight of the surfactant based on { HEAD ~ the amount } of { TAIL ~ acid }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL