APA-čujuhus (7. p.)
Summers, R. S., & Hillman, R. A. (2011). Contract and related obligation: Theory, doctrine, and practice (6th ed.). Thomson/West.
Chicago-čujuhus (17. p.)
Summers, Robert S., juo Robert A. Hillman. Contract and Related Obligation: Theory, Doctrine, and Practice. 6th ed. St. Paul, MN: Thomson/West, 2011.
MLA-čujuhus (9. p.)
Summers, Robert S., juo Robert A. Hillman. Contract and Related Obligation: Theory, Doctrine, and Practice. 6th ed. Thomson/West, 2011.
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