Parsley (Edwards) TL. Review of the phantom respondents: opinion surveys and political representation. J Off Stat. 1994;10(3):351-5.
Kaufman DW, Kelly JP, Johannes CB, Sandler A, Harmon D, Stolley PD, Shapiro S. Acute thrombocytopenic purpura in relation to the use of drugs. Blood. 1993 Nov 1;82(9):2714-8.