APA (7th ed.) Zitazioa
Robèrt, K. (2002). The natural step story: Seeding a quiet revolution. New Society Publishers.
Chicago Style (17th ed.) Zitazioa
Robèrt, Karl-Henrik. The Natural Step Story: Seeding a Quiet Revolution. Gabriola Island, B.C.: New Society Publishers, 2002.
MLA (9th ed.) Zitazioa
Robèrt, Karl-Henrik. The Natural Step Story: Seeding a Quiet Revolution. New Society Publishers, 2002.
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