Bjornavold, Jens Making learning visible : Identification, assessment and recognition of non-formal learning in Europe / Jens Bjornavold. - Thesanoloniki : Luxembourg : CEDEFOP; European Communities, 2000. - 224 p. - CEDEFOP Reference document . ISBN: 9289600063 No. de Clasificación Universal Decimal: 374 (4) =20 "2000" BJO.