TY - RPRT TI - Circular of the Bureau of Standards no. 487: density of solids and liquids AU - Hidnert, Peter AU - Peffer, Elmer L PY - 1950 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS CIRC 487 DO - 10.6028/NBS.CIRC.487 ER -