TY - GEN AU - Bowen, R L C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1968-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.RPT.9916 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1968 TI - X-ray-opaque reinforcing fillers for composite materials ::progress report ER -