APA (7th ed.) Citation

Geological Survey (U.S.) & ProQuest (Firm). (1910). [Geological Survey bulletin 421; Results of spirit leveling in Illinois, 1896-1908]. [publisher not identified].

Chicago Style (17th ed.) Citation

Geological Survey (U.S.) and ProQuest (Firm). [Geological Survey Bulletin 421; Results of Spirit Leveling in Illinois, 1896-1908]. Washington: [publisher not identified], 1910.

MLA (9th ed.) Citation

Geological Survey (U.S.) and ProQuest (Firm). [Geological Survey Bulletin 421; Results of Spirit Leveling in Illinois, 1896-1908]. [publisher not identified], 1910.

Warning: These citations may not always be 100% accurate.