PT - JOURNAL ARTICLE AU - A Cartwright AU - W Tucker TI - An experiment with an advance letter of an interview inquiry. AID - 10.1136/jech.23.4.241 DP - 1969 Nov 01 TA - British Journal of Preventive & Social Medicine PG - 241--243 VI - 23 IP - 4 4099 - http://jech.bmj.com/content/23/4/241.short 4100 - http://jech.bmj.com/content/23/4/241.full SO - Br J Prev Soc Med1969 Nov 01; 23