id	author	title	date	pages	extension	mime	words	sentence	flesch	summary	cache	txt
crl-12984	Perk, Lawrence J.	Secondary Publications in Education: A Study of Duplication	1977	6	.pdf	application/pdf	3023	143	61	In an education- psychology library the user was refer- ring to Education Index, ERIC's Cur- rent Index to Journals in Education, and Psychological Abstracts. PA ............ s 100 ::s z 0 1969 1970 1971 1972 1973 1974 Figure 1 Growth of Coverage by Three Bibliographic Services: Education Index ( EI ) , Current Index to Journals in Education ( CI]E), and Psycho- logical Abstracts ( P A) this study-namely, ( 1) editorial policy, ( 2) the overlap and non-overlap of cov- erage, ( 3) several indicators of the core titles, ( 4) the size of coverage, and ( 5) the subject nature of the above.	cache/crl-12984.pdf	txt/crl-12984.txt