Lindquist, E.F.Design and Analysis of Experiments in Psychology and Education.New York: Houghton-Mifflin Company, 1953.
2.
Marshall, M.V. and Simpson, E.W."Vocational Choice and College Grades" , Journal of Educational Research , XXVII (1943), 303-305.
3.
Weitz, Henry, "A Report on Placement Test Performance of Freshmen Entering Duke University in I953", Staff Research Report Number 4Duke University Bureau of Testing and Guidance, i November 1953.
4.
Weitz, Henry and Droege, Robert."A Study of the Relationships between Placement Test Scores and Academic Performance". Unpublished study of the Duke University Bureau of Testing and Guidance, 1952.
5.
Zorbaugh, G.S.M. and Kuder, G.F."College Grades and Vo-Tests cational Motives". School and Society , XLVI (1937), 62-64. Tests
6.
American Council on EducationPsychological Examination for College Freshmen.1949 edition.
7.
The Cooperative English Test: Mechanics of Expression, Test A-2, Form Y.
8.
The Cooperative English Test: Reading Comprehension, Test C-2, Higher level, Form Y.
9.
The Duke University Department of Mathematics Placement Test, Form C-I.
