TY - GEN AU - Peter L M Heydemann C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1975-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.IR.75-648 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1975 TI - Ultrasonic interferometer manometer: ER -