APA (7th ed.) Citation

Oppenheim, E. P., & Grefé, W. (2007). Mr. Grex of Monte Carlo. Project Gutenberg.

Chicago Style (17th ed.) Citation

Oppenheim, E. Phillips, and Will Grefé. Mr. Grex of Monte Carlo. Project Gutenberg, 2007.

MLA (9th ed.) Citation

Oppenheim, E. Phillips, and Will Grefé. Mr. Grex of Monte Carlo. Project Gutenberg, 2007.

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