Early Childhood Longitudinal Study, Kindergarten Class of 2010-11 (ECLS-K:2011). User's Manual for the ECLS-K:2011 Kindergarten Data File and Electronic Codebook, Public Version. NCES 2015-074.
作者: Karen Tourangeau , Mary C. Hagedorn , Thanh Lê , Christine Nord , Michelle Najarian
National Center for Education Statistics National Center for Education Statistics. Available from: ED Pubs. P.O. Box 1398, Jessup, MD 20794-1398. Tel: 877-433-7827; Web site: http://nces.ed.gov/