APA (7th ed.) Citation

Gurley, firm, math. instr. makers, Troy. (1921. W. & L.E. Gurley). (1910). A manual of the principal instruments used in American engineering and surveying / manufactured by W. & L. E. Gurley, Troy, N.Y (44th ed.). W. & L. E. Gurley.

Chicago Style (17th ed.) Citation

Gurley, firm, math. instr. makers, Troy. (1921. W. & L.E. Gurley). A Manual of the Principal Instruments Used in American Engineering and Surveying / Manufactured by W. & L. E. Gurley, Troy, N.Y. 44th ed. Troy, N. Y.: W. & L. E. Gurley, 1910.

MLA (9th ed.) Citation

Gurley, firm, math. instr. makers, Troy. (1921. W. & L.E. Gurley). A Manual of the Principal Instruments Used in American Engineering and Surveying / Manufactured by W. & L. E. Gurley, Troy, N.Y. 44th ed. W. & L. E. Gurley, 1910.