Williams VSL. The "unbiased" anchor: bridging the gap between DIF and item bias. Appl Meas Educ. 1997;10(3):253-67. doi: 10.1207/s15324818ame1003_4
Johannes CB, Caro JJ, Hartz SC, Marrs R. Adverse effects of ovulatory stimulants: a review. Assist Reprod Rev. 1993;3:68-74.