RT Journal Article SR Electronic T1 THE SIGNIFICANCE OF THE DECLINING BIRTH-RATE-A REPLY JF Science JO Science FD American Association for the Advancement of Science SP 533 OP 536 DO 10.1126/science.50.1302.533 VO 50 IS 1302 A1 Hayes, Ellen YR 1919 UL http://science.sciencemag.org/content/50/1302/533.abstract AB