How do I cite musical pieces?

Question:

How do I cite musical pieces?

It's not really "citing" per se; I'm writing a paper on the Mozart Effect (my paper is about how it doesn't exist), and I want to know what I have to do when I write "Mozart's Sonata for Two Pianos in D Major." Do I put "Sonata for Two..." in quotes, or italicize it, or what?

Best Answer - Chosen by Asker: I assume that you are not asking about a bibliographic citation, but rather a reference to a composition in the text. Here is a little guide for Mozart:

Use italics for titles of operas:

Le Nozze di Figaro

Use quotation marks for songs:

"An die Freude"

For sonatas, concerti, and symphonies, do not use italics or quotes, but include the K. number (from the Mozart catalog):

Mozart's Sonata in D Major for two pianos, K. 448

The exception for this would be in the work has a nick name, such as Symphony in C Major, "Jupiter"