Overview of Special Issue.
James AllanNicholas J. BelkinPaul N. BennettJamie CallanCharles L. A. ClarkeFernando DiazSusan T. DumaisNicola FerroDonna HarmanDjoerd HiemstraIan RuthvenTetsuya SakaiMark D. SmuckerJustin ZobelPublished in: SIGIR Forum (2017)