TY  - JOUR
T1  - Probing 'Don't Know' Answers: Effects on Survey Estimates and Variable Relationships
AU  - Sanchez, Maria Elena
AU  - Morchio, Giovanna
PY  - 1992
DO  - 10.1086/269337
SP  - 454
EP  - 474
JO  - Public Opinion Quarterly
VL  - 56
IS  - 4
SN  - 0033-362X
ER  -