Hobbs, W. H. Earth Features and Their Meaning An Introduction to Geology for the Student and the General Reader.
Chicago-viite (17. p.)Hobbs, William Herbert. Earth Features and Their Meaning An Introduction to Geology for the Student and the General Reader.
MLA-viite (9. p.)Hobbs, William Herbert. Earth Features and Their Meaning An Introduction to Geology for the Student and the General Reader.
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