Abstract

Get full access to this article
View all access options for this article.
References
1.
Abell
A. T.
Words functioning simultaneously as operant and respondent reinforcers: preliminary study . Psychological Reports , 1969 , 24 , 123 –133 .
2.
Siegel
S.
Nonparametric statistics for the behavioral sciences . New York : McGraw-Hill , 1956 .
3.
Underwood
B. J.
Experimental psychology . (2nd ed. ) New York : Appleton-Century-Crofts , 1966 .
