Duggal, S. (2016). Surveying Vol.2 (4.). Mc Graw Hill Education.
Chicago-čujuhus (17. p.)Duggal, S.K. Surveying Vol.2. 4. chennai: Mc Graw Hill Education, 2016.
MLA-čujuhus (9. p.)Duggal, S.K. Surveying Vol.2. 4. Mc Graw Hill Education, 2016.
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