| CPC C09K 8/06 (2013.01) [C09K 8/145 (2013.01); C09K 8/22 (2013.01); C09K 2208/12 (2013.01)] | 18 Claims |

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1. A combination clay stabilizer comprising:
an alkali metal asphalt sulfonate; and
a quaternary ammonium salt, wherein the quaternary ammonium salt is a choline salt.
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