TY - RPRT TI - Physical testing of polymers for use in circulatory assist devices : first annual report July 1978 AU - Penn, Robert W AU - McKenna, Gregory B PY - 1978 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS IR 79-1741 DO - 10.6028/NBS.IR.79-1741 ER -