TY  - RPRT
TI  - Integrating knowledge for the identification of cracks in concrete using an expert system shell and extensions 
AU  - Kaetzel, L J
AU  - Clifton, J R
AU  - Bentz, D P
PY  - 1989
PB  - National Institute of Standards and Technology
CY  - Gaithersburg, MD
SN  - NIST IR 89-4206
DO  - 10.6028/NIST.IR.89-4206
ER  -