Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. - PubMed - NCBI

Proc Natl Acad Sci U S A. 2015 Jan 27;112(4):1232-7. doi: 10.1073/pnas.1418490112. Epub 2014 Dec 22. Clinical Trial; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.