PT - JOURNAL ARTICLE ED - , TI - RADIUM AND HELIUM AID - 10.1126/science.18.449.186 DP - 1903 Aug 07 TA - Science PG - 186--187 VI - 18 IP - 449 4099 - http://science.sciencemag.org/content/18/449/186.short 4100 - http://science.sciencemag.org/content/18/449/186.full SO - Science1903 Aug 07; 18