SKINNER, B. J. (1987). Physical geology - Brian J. Skinner, Stephen C. Porter. John Wiley & Sons.
Lua i Stíl Chicago (17ú heag.)SKINNER, Brian J. Physical Geology - Brian J. Skinner, Stephen C. Porter. John Wiley & Sons, 1987.
Lua MLA (8ú heag.)SKINNER, Brian J. Physical Geology - Brian J. Skinner, Stephen C. Porter. John Wiley & Sons, 1987.
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