Hits 1-3 within 3 documents
Hits 1-3 within 3 documents
Author(s): Ulbrich, Klaus.- 1984. 27p.
Editor(s): Zentralinstitut für Jugendforschung (ZIJ).- 1975. 9p.
Author(s): Gerth, Werner; Burkhardt, Erwin; Bernard, Günter; Bertram, Barbara; Bonus, Hans; Heinrichs, W.; Höpfner, E..- 1970. 62p.