(Sense, 2009) Düggeli, Albert; Heinzer, Sarah; Oser, Fritz; Curcio, Gian-Paolo; Oser, Fritz; Renold, Ursula; John, Ernst G.; Winther, Esther; Weber, Susanne [in: VET Boost: Towards a Theory of Professional Cmpetencies. Essays in Honor of Frank Achtenhagen]