MIT School of Architecture and Planning
http://sap.mit.edu/resources/portfolio/grease

MIT CoLab Radio
http://colabradio.mit.edu/category/8-completed-project-feeds/waste-pickers-movement-in-sao-paulo-2

MNCR (Brazil wastepicker Union) News in portuguese
Cooperativas usam óleo de cozinha como combustível
http://www.mncr.org.br/artigos/cooperativas-usam-oleo-de-cozinha-como-combustivel