Question

For MLA style citation/Works Cited, what is the preferred way of indicating a work is a play/drama?

Answer 1

This is an excellent resource for learning about MLA formatting http://owl.english.purdue.edu/owl/resource/747/12/
Usually the type of work is indicated in MLA by what you do with the title. When you are writing your paper a play is italicized, therefore you italicize it in the citation.
Here is an example of an MLA play citation: Italicized words will appear like /this/

Shakespeare, William. /The Tragedy of King Richard II/. The Necessary Shakespeare. 3rd ed. Ed. David Bevington. New York: Pearson 2009. 331-369. Print.