Darwin, C. (1945). Darwin on humus and the earthworm: The formation of vegetable mould through the action of worms with observations on their habits. Faber & Faber.
Chicago-viite (17. p.)Darwin, Charles. Darwin on Humus and the Earthworm: The Formation of Vegetable Mould Through the Action of Worms with Observations on Their Habits. London: Faber & Faber, 1945.
MLA-viite (8. p.)Darwin, Charles. Darwin on Humus and the Earthworm: The Formation of Vegetable Mould Through the Action of Worms with Observations on Their Habits. Faber & Faber, 1945.
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