EPA Method 548.1 Internal Standard Back Catalog number: 30078 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 677865 Thiencarbazone-methyl, 10.0 µg/ml, Acetonitrile, Price on request P-442N Dimethyl phosphate, 10mg Price on request 71511 3-Ethylphenol Price on request