Generic titles like Symphony, Sonata, or Concerto should not be italicized or put in quotations. Pitches and tonal centers in titles should be capitalized. Opus and other catalog numbers are preceded by a comma and typically abbreviated. "Opus" is generally abbreviated "Op."
Mozart's Piano Sonata No. 16 in C Major, K. 525
Symphony No. 2 in D major, Op. 73 by Johannes Brahms
Mendelssohn's Violin Concerto in E Minor, Op. 64
Elliott Carter's String Quartet No. 1
Requiem in D Minor, Op. 48
If a work has also has a descriptive title, the description should be listed at the end, in italics, and preceded by a comma.
Shostakovich's Symphony No. 7 in C Major, Op. 60, Leningrad
Beethoven's Sonata No. 21 in C Major, Waldstein
Compositions with a personalize title, including song titles that are not part of a larger work, should be italicized.
Boléro by Ravel
Dichterliebe by Robert Schumann
The Rite of Spring by Stravinsky
Carl Orff wrote Carmina Burana in 1936
Black Angels was written by George Crumb
For arias and songs from larger works, the title of the song/aria should be put in quotation marks. The larger work should be italicized when used.
"Sempre Libera" from La Traviata by Verdi
"Ich Grolle Nicht" from Dichterliebe
"Largo al factotum della cittá" from The Barber of Seville