TY - RPRT TI - The microwave frequency standard at the Central Radio Propagation Laboratory AU - George, W D AU - Lyons, H AU - Freeman, J J AU - Shaull, J M PY - 1947 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS CRPL 8-1_9-4 DO - 10.6028/NBS.CRPL.8-1_9-4 ER -