Miller-Klein, Jan. Gardening for Butterflies, Bees and other beneficial insectsISBN 978-0-9555288-0-4 has large section on green and brown roofs and brownfields, including how to make your own, with contributions from several UK practitioners.
Scholz-Barth, Katrin. "Harvesting $ from Green Roofs: Green Roofs Present a Unique Business Opportunity with Tangible Benefits for Developers." Urban land 64.6 (2005): 83-7.