Hobbs, R. C., & Smithson, R. (1981). Robert Smithson: Sculpture / Robert Carleton Hobbs. With contrib. by. Cornell Univ. Press.
Chicago Style (17. basım) AtıfHobbs, Robert Carleton, ve Robert Smithson. Robert Smithson: Sculpture / Robert Carleton Hobbs. With Contrib. by. Ithaca [u.a.]: Cornell Univ. Press, 1981.
MLA (8th ed.) AtıfHobbs, Robert Carleton, ve Robert Smithson. Robert Smithson: Sculpture / Robert Carleton Hobbs. With Contrib. by. Cornell Univ. Press, 1981.
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