MLA

Twain, Mark, 1835-1910. Some thoughts on the science of onanism / by Mark Twain. Being an address delivered ... before the members of the ... Stomach Club ... Paris ... 1879. 1952. https://collections.library.yale.edu/catalog/2004873.

APA, 6th edition

Twain, Mark, 1835-1910. (1952)[Some thoughts on the science of onanism / by Mark Twain. Being an address delivered ... before the members of the ... Stomach Club ... Paris ... 1879]. https://collections.library.yale.edu/catalog/2004873.