Until we combine our own resources, the IDS program page has a great accumulation of information including links to grad schools and study abroad options around the globe.
IDS Resources
City Farmer - an urban agriculture resource centre; enormous search engine
RUAF - Resource Centres on Urban Agriculture and Food Security
Arturo Escobar Index - the Arturo Escobar website (access to most of his recent work in PDF files, as well as some explanatory notes about his research interests)

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