RT Journal Article SR Electronic T1 In Reply: The Overhead Question JF Science JO Science FD American Association for the Advancement of Science SP 12 OP 12 DO 10.1126/science.249.4964.12 VO 249 IS 4964 A1 Eldridge, Roger YR 1990 UL http://science.sciencemag.org/content/249/4964/12.1.abstract AB