Havil, J. (2005). GAMMA: EXploring Euler`s Constant (1st.). ICFAI University Press.
Chicago-čujuhus (17. p.)Havil, Julian. GAMMA: EXploring Euler`s Constant. 1st. Hyderabad: ICFAI University Press, 2005.
MLA-čujuhus (9. p.)Havil, Julian. GAMMA: EXploring Euler`s Constant. 1st. ICFAI University Press, 2005.
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