APA (7th ed.) Citation

Oppenheim, E. P. (2006). The Box with Broken Seals. Project Gutenberg.

Chicago Style (17th ed.) Citation

Oppenheim, E. Phillips. The Box with Broken Seals. Project Gutenberg, 2006.

MLA (9th ed.) Citation

Oppenheim, E. Phillips. The Box with Broken Seals. Project Gutenberg, 2006.

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