What is man? :
and other essays /
by Mark Twain.

APA Citation

Twain, M. (1917). What is man?: and other essays. New York: Harper and Bros..

MLA Citation

Twain, Mark, 1835-1910. What Is Man?: And Other Essays. New York: Harper and Bros., 1917.

Warning: These citations may not always be complete (especially for serials).