APA (7th ed.) Citation

Nymeyer, R., & Halliday, W. R. (1991). Carlsbad Cavern: The early years. Carlsbad Cavern, Guadalupe Mountains Association.

Chicago Style (17th ed.) Citation

Nymeyer, Robert, and William R. Halliday. Carlsbad Cavern: The Early Years. Carlsbad, New Mexico: Carlsbad Cavern, Guadalupe Mountains Association, 1991.

MLA (9th ed.) Citation

Nymeyer, Robert, and William R. Halliday. Carlsbad Cavern: The Early Years. Carlsbad Cavern, Guadalupe Mountains Association, 1991.

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