RT Journal Article SR Electronic T1 The End of the Beginning JF Science JO Science FD American Association for the Advancement of Science SP 459 OP 459 DO 10.1126/science.215.4532.459 VO 215 IS 4532 A1 MURRAY, BRUCE YR 1982 UL http://science.sciencemag.org/content/215/4532/459.abstract AB