1. Baker, R.,: A primer of Oil Well Drilling, U of Texas, (1996)
2. Breiman, L., Friedman, J.H, Olshen, R..A., Stone, C. J.: Classification and Regression Trees, Wadsworth (1984)
3. Apte, C, Damerau, F. and Weiss, S. H.: Automated Learning of Decision Rules for Text Categorization, ACM Transactions on Information Systems, Vol. 12, No. 3,(July 1994.)
4. Harabagiu, Sanda M, Moldavan Dan I.: TextNet-A Text Based Intelligent System,: Natural Language Engineering 3(2/3): 171–190 (1997)
5. Irrgang, R., Irrgang H., Kravis, S., Irrgang S., Thonhauser, G., Wrightstone A., Nakagawa, E., Agawani, M., Lollback, P., Gabler, T., Maidla, E.,: Assessment of Risk and Uncertainty for Field Developments: Integrating Reservoir and Drilling Expertise: SPE Annual Technical Conference and Exhibition, New Orleans, USA, SPE 71419, Oct, (2001)