McDonnell, K. (1968). Enquiring into the earth. Longmans.
Chicago-čujuhus (17. p.)McDonnell, K.S. Enquiring into the Earth. Melbourne: Longmans, 1968.
MLA-čujuhus (9. p.)McDonnell, K.S. Enquiring into the Earth. Longmans, 1968.
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