4Resnick L B. Principles of Learning for Effort - based Education [ EB/OL]. Abridged version of the E - Book excerpted from the CD - ROM : Principles of Learning : Study Tools for Educators Version 3. 0, 2002.
5Genichi Taguchi, Rajesh Jugulum. The Mahalanobis - Taguchi Strategy [ M]. John Wiley & Sons, Inc. ,2002.