O'Connor, R. (1971). The oil barons: Men of greed and grandeur (3. print.). Little, Brown.
Chicago-viite (17. p.)O'Connor, Richard. The Oil Barons: Men of Greed and Grandeur. 3. print. Boston [u.a.]: Little, Brown, 1971.
MLA-viite (8. p.)O'Connor, Richard. The Oil Barons: Men of Greed and Grandeur. 3. print. Little, Brown, 1971.
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