1-Butylpyridinium bis[(trifluoromethyl)sulfonyl]azanide; N-butylpyridinium bis((trifluoromethyl)sulfonyl)imide; 1-Butylpyridinium salt with 1,1,1-trifluoro-N-[(trifluoromethyl)sulfonyl]methanesulfonamide; N-Butylpyridinium bis(trifluoromethanesulfonyl)imide