TY - RPRT TI - Standardization of thermal emittance measurements : progress report no. 18, January 1 - March 31, 1963 AU - Joseph, Horace M AU - Harrison, William N PY - 1963 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS report ; 8037 DO - 10.6028/NBS.RPT.8037 ER -