TY - GEN AU - Siegwarth, J D C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1977-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.TN.698 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1977 TI - Cryogenic fluids density reference system ::provisional accuracy statement ER -