Leyendecker, Birgit, Alexandru Agache, and Stefanie Madsen. “Nationale Untersuchung Zur Bildung, Betreuung Und Erziehung in Der frühen Kindheit (NUBBEK) – Design, Methodenüberblick, Datenzugang Und Das Potenzial Zu Mehrebenenanalysen: NUBBEK – a National German Study on Early Childhood Education and Care: Design, Methods Overview, Data Access, and the Potential for Multilevel Analyses”. Journal of Family Research 26, no. 2 (September 1, 2014): p. 244–258. Accessed May 3, 2024. https://ubp.uni-bamberg.de/jfr/index.php/jfr/article/view/17.