. EMPLOYMENT PSYCHOLOGY 
research work on the vocation in question so that he can 
use positive findings and avoid whatever proved worthless. 
Published studies of this sort are to be found in psychologi- 
cal journals, trade magazines, volumes of research, and in 
miscellaneous publications, reference to which may be found 
in bibliographies. His acquaintance with other research 
workers often enables the investigator to learn of results 
obtained in unpublished studies. 
General test publications. These need not relate to the 
vocation under study but may cover the general field of 
tests and their evaluation. No matter how well acquainted 
he is with the field of psychological tests in general, a review 
of the literature will assure the investigator that he has not 
overlooked any applicable tests. 
Since psychological tests are an outgrowth of standard 
laboratory experiments in psychology, it will repay effort 
to refer to some of the laboratory manuals. Among these 
are Titchener (200), Myers (122), Sanford (161), Lang- 
feld and Allport (100), Schultze (163), and Scripture 
(167), as well as numerous untranslated German volumes. 
Manuals of psychological tests constitute a second source 
of information. Some of the best known are those of Whip- 
ple (220), Franz (54), Woodworth and Wells (225), 
Dewey, Child, and Ruml (44), Pintner and Paterson (139), 
Giese (61), Downey (48), Ballard (35), Terman (185), 
Burt (22), Trabue and Stockbridge (205), Stern (174), 
and Lipmann (103). Considerable test material may also 
be found in Link (ror), Burtt (23), and Partridge (127), 
and in the report on “Psychological Examining in the United 
States Army” (228). A number of volumes on educational 
measurements and some of the studies published in the 
Psychological Monographs and the Archives of Psychology 
contain valuable test material. Material may also be found 
in the catalogs of the C. H. Stoelting Company (Chicago), 
World Book Company (Yonkers), and E. Zimmermann 
(Leipzig and Berlin). 
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