APA
Holmberg J., Timberlake L. & Bass S. (1991). Defending The Future : A Guide To Sustainable Development. : Earthscan Publications Ltd. London/IIED.
Chicago
Holmberg J, Timberlake L and Bass S. 1991. Defending The Future : A Guide To Sustainable Development. : Earthscan Publications Ltd. London/IIED.
Harvard
Holmberg J., Timberlake L. and Bass S. (1991). Defending The Future : A Guide To Sustainable Development. : Earthscan Publications Ltd. London/IIED.
MLA
Holmberg J, Timberlake L and Bass S. Defending The Future : A Guide To Sustainable Development. : Earthscan Publications Ltd. London/IIED. 1991.