TY - RPRT TI - Friction and wear characteristics of molecular compound classes from lubricating base oils : part 1 separation and chemical characterization AU - Hsu, S M AU - Gates, R S PY - 1984 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS IR 84-2821 DO - 10.6028/NBS.IR.84-2821 ER -