TY - RPRT TI - Circular of the Bureau of Standards no. 93 2nd edition: United States government specification for iron-oxide and iron-hydroxide paints PY - 1922 PB - National Bureau of Standards CY - Gaithersburg, MD SN - NBS CIRC 93e2 DO - 10.6028/NBS.CIRC.93e2 ER -