TY - GEN AU - Stefan Leigh AU - N Alan Heckert C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1994-01-01 05:01:00 DO - https://doi.org/10.6028/NIST.IR.5387 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1994 TI - Graphical analysis of the CCRl Portland cement proficiency sample database (samples 1-72): ER -