Plunkett Foundation for Co-operative Studies & Horace Plunkett Foundation. Year book of agricultural co-operation. Routledge & Sons.
Chicago-referens (17:e uppl.)Plunkett Foundation for Co-operative Studies och Horace Plunkett Foundation. Year Book of Agricultural Co-operation. London: Routledge & Sons.
MLA-referens (8:e uppl.)Plunkett Foundation for Co-operative Studies och Horace Plunkett Foundation. Year Book of Agricultural Co-operation. Routledge & Sons.
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