%0 Journal Article %A A Cartwright %A W Tucker %T An experiment with an advance letter of an interview inquiry. %D 1969 %R 10.1136/jech.23.4.241 %J British Journal of Preventive & Social Medicine %P 241-243 %V 23 %N 4 %U https://jech.bmj.com/content/jech/23/4/241.full.pdf