Richardson Thomas S, Robins James M, Wang Linbo
Department of Statistics, University of Washington, Seattle, Washington 98195, U.S.A.
Department of Biostatistics, Harvard School of Public Health, 677 Huntington Ave., Boston, Massachusetts 02115, U.S.A.
Biometrics. 2018 Jun;74(2):403-406. doi: 10.1111/biom.12784. Epub 2017 Nov 2.