@misc{1129826, author = {Paul Stutzman and Alan Heckert}, title = {Certification of standard reference material SRM2687a, Portland cement clinker:}, year = {2019}, month = {2019-03-01 05:03:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NIST.SP.260-195}, language = {en}, }