APA (7th ed.) Citation

Maidl, B., Thewes, M., & Maidl, U. Handbook of tunnel engineering. Ernst.

Chicago Style (17th ed.) Citation

Maidl, Bernhard, Markus Thewes, and Ulrich Maidl. Handbook of Tunnel Engineering. Berlin: Ernst.

MLA (9th ed.) Citation

Maidl, Bernhard, et al. Handbook of Tunnel Engineering. Ernst.