?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adissertation&rft.aulast=Popma&rft.au=Popma%2C+Vincent&rft.aufirst=Vincent&rft.title=Support+base+for+hydrogen+economy+Groningen-Assen%3A+Motives+and+regional+impact+of+firms+implementation+of+the+hydrogen+economy&rft.tpages=45&rft.degree=Master&rft.date=2021