Pigford, D., & .Baur, G. R. (1990). Expert systems for business: Concepts and applications : featuring VP-Expert. Boyd & Fraser Pub. Co..
Chicago-viite (17. p.)Pigford, Darleen, ja Gregory R. .Baur. Expert Systems for Business: Concepts and Applications : Featuring VP-Expert. Boston: Boyd & Fraser Pub. Co., 1990.
MLA-viite (9. p.)Pigford, Darleen, ja Gregory R. .Baur. Expert Systems for Business: Concepts and Applications : Featuring VP-Expert. Boyd & Fraser Pub. Co., 1990.
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