References
- BADDELEY , A. D. , THOMSON , N. , and BUCHANAN , M. , 1975 , Word length and the structure of short-term memory . Journal of Verbal Learning and Verbal Behavior , 14 , 575 – 589 .
- CONRAD , R. , and HULL , A. J. , 1968 , The preferred layout for numeral data–entry keysets . Ergonomics , 11 , 165 – 173 .
- DEININGER , R. L. , 1960 , Human factors engineering studies of the design and use of pushbutton telephone sets . Bell System Technical Journal , 39 , 995 – 1012 .
- KLEMMER , F. T. , 1971 , Keyboard entry . Applied Ergonomics , 2 , 2 – 6 .
- SHIBEL , R. , 1972 , Data entry devices and procedures . In Human Engineering Guide to Equipment Design ( Edited by H. P. COTT and R. G. KINKADE ) ( Washington DC , AMERICAN INSTITUTE FOR RESEARCH ).