Levi, H. (1960). Foundations of geometry and trignometry. Prentice Hall.
Chicago-čujuhus (17. p.)Levi, Howard. Foundations of Geometry and Trignometry. Englewood Cliffs: Prentice Hall, 1960.
MLA-čujuhus (9. p.)Levi, Howard. Foundations of Geometry and Trignometry. Prentice Hall, 1960.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.