Titles are really confusing!
If you use the exact same title for all the various books, CDs, scores, etc. related to a piece, then you know what to search for--that is a uniform title.
Uniform titles can also be used to show groups of pieces put together in a published work (like 3 sonatas in one volume). Like this:
Quartets, strings
Chamber music. Selections
Works
That last one is important. If we have a complete works edition of a given composer, you'll find it listed under "Works." The same would be used for an edition of CDs of every single work by a given composer.
Uniform titles come in two flavors:
Distinctive titles are titles that are unique--for example, there's only one Firebird by Stravinsky. However, the title appears in its original language. So for example, Firebird appears as Zhar-ptitsa:
Stravinsky, Igor, 1882-1971. Zhar-ptitsa
Mozart, Wolfgang Amadeus, 1756-1791. Nozze di Figaro
Orff, Carl, 1895-1982. Carmina Burana
Corigliano, John, 1938-. Fern Hill
Form titles use the common genre names familiar to most musicians--particularly with instrumental music--like Sonatas, Masses, Quartets, etc.
Form titles have several common bits:
Here are a couple of examples:
Beethoven, Ludwig van, 1770-1827. Quartets, strings, no. 16, op. 135, F major
Bach, Johann Sebastian, 1685-1750. Masses, BWV 232, B minor
"Extra Information" can be used for a variety of useful bits of information. For example:
Barber, Samuel, 1910-1981. Reincarnations. Mary Hynes
Purcell, Henry, 1659-1695. Fairy queen. Vocal score
Palestrina, Giovanni Pierluigi da, 1525?-1594. Masses, book 3. Missa brevis
Orff, Carl, 1895-1982. Carmina Burana. Libretto. English and Latin