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Lua i Stíl Chicago (17ú heag.)CHENG, LIU. Soil Propertis Lesting, Measurement And Evaluation Cheng Liu & Jack B. Evett. Prentice - Hall, 1984.
Lua MLA (8ú heag.)CHENG, LIU. Soil Propertis Lesting, Measurement And Evaluation Cheng Liu & Jack B. Evett. Prentice - Hall, 1984.
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