TY - GEN AU - Curtiss, Leon F C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1949-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.CIRC.476 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1949 TI - Circular of the Bureau of Standards no. 476::measurements of radioactivity ER -