APA (7th ed.) Citation

Allen, J. L. (2013). The Doctor's Christmas Eve. Project Gutenberg.

Chicago Style (17th ed.) Citation

Allen, James Lane. The Doctor's Christmas Eve. Project Gutenberg, 2013.

MLA (9th ed.) Citation

Allen, James Lane. The Doctor's Christmas Eve. Project Gutenberg, 2013.

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