Visionary Leadership as a Tool for Eco-efficiency in Organiations : Developing an Integrated Conceptual Model - Vinnari, Markus; Luukkanen, Jyrki; Kaivo-oja, Jari (fi=Turun yliopisto. Turun kauppakorkeakoulu|en=University of Turku, Turku School of Economics|, 2019)