TY  - JOUR
T1  - Tracking opinion over time: A method for reducing sampling error
AU  - Green, Donald P.
AU  - Gerber, Alan S.
AU  - Boef, Suzanna L. de
PY  - 1999
DO  - 10.1086/297710
SP  - 178
EP  - 192
JO  - Public Opinion Quarterly
VL  - 63
IS  - 2
SN  - 0033-362X
ER  -