International Federation of Organic Agriculture Movements (IFOAM). IFOAM Internal Letter. Tholey-Theley: IFOAM.
Chicago-viite (17. p.)International Federation of Organic Agriculture Movements (IFOAM). IFOAM Internal Letter. Tholey-Theley: IFOAM.
MLA-viite (8. p.)International Federation of Organic Agriculture Movements (IFOAM). IFOAM Internal Letter. Tholey-Theley: IFOAM.
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