GuilfordJ. P. (Ed.) Printed Classification Tests. Army Air Forces Aviation Psychology Research Program,Report No. 5. Washington: U. S. Government Printing Office, 1947.
2.
ThurstoneL. L.Multiple Factor Analysis. Chicago: University of Chicago Press, 1947.
3.
ZimmermanWayne S. “A Simple Graphical Method for Orthogonal Rotation of Axes.” Psychometrika, XI (1946), 51–55.