@misc{1137981,
  author = {Jeffrey W Bullard},
  title = {Virtual cement and concrete testing laboratory ::educational version 2.0 user guide},
  year = {2010},
  month = {2010-01-01 05:01:00},
  publisher = {, National Institute of Standards and Technology, Gaithersburg, MD},
  doi = {https://doi.org/10.6028/NIST.IR.7707},
  language = {en},
}