[roel_v]

English-language ones I could easily find are e.g. http://www.ncbi.nlm.nih.gov/pubmed/17009190 and http://onlinelibrary.wiley.com/doi/10.1111/j.1748-0361.1999.... (both first page Google results for 'depression in rural areas'). I was specifically thinking about a study in the Netherlands who showed the same, but there have been a lot of studies on this subject so it's quite easy to find literature.