Bond JC, Geller RJ, White KO, Hatch EE, Rothman KJ, Wise LA. Concordance of self-reported sexual intercourse frequency between members of mixed-sex couples attempting conception. Can J Hum Sex. 2022 Dec;31(3):342-53. doi: 10.3138/cjhs.2021-0059
Fleming A, Goatman KA, Sharp PF, Styles CJ, Wikes WN, Olson JA. A large scale validation of automated grading. Eur J Ophthalmol. 2009 May 1;19(3):504.