PT - JOURNAL ARTICLE AU - , TI - Review AID - 10.2307/4443224 DP - 1970 Nov 01 TA - The American Biology Teacher PG - 499--500 VI - 32 IP - 8 4099 - http://abt.ucpress.edu/content/32/8/499.6.short 4100 - http://abt.ucpress.edu/content/32/8/499.6.full