TY - JOUR A1 - Rackin, H. A1 - Morgan, S.P. T1 - Prospective versus retrospective measurement of unwanted fertility: Strengths, weaknesses, and inconsistencies assessed for a cohort of US women Y1 - 2018 DO - 10.4054/DemRes.2018.39.3 VL - 39 IS - 3 ER -