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Using the Music Library

Work Numbers for Selected Composers

"Work numbers" (also known as "thematic catalog numbers," or less accurately as "opus numbers"), are numbering systems used to catalog a composer's works. The most common form of these are "opus" numbers, generally assigned by the composers themselves for their own works (for example, Beethoven, Brahms, Schumann, and Prokofiev assigned opus numbers).

In many cases, however, the composer did not assign any numbers to his or her own works, or did so incompletely and/or inconsistently (for example, Schubert). In such cases, sooner or later one or more scholars will take on the task of cataloging that composer's works and assigning numbers to them. By convention, such numbers do not use the word "opus." In some cases the scholar's name will be used for the numbering system (such as Köchel for Mozart, Deutsch for Schubert, Hoboken for Haydn). In other cases the term is an abbreviation of a scholarly work (such as "BWV" for Bach-Werke-Verzeichnis). In the case of composers who assigned their own opus numbers, but left some works unnumbered, works without opus numbers may be given WoO ("Werke ohne Opus") numbers by scholars.

Thematic catalogs for composers, with work numbers, can be found in Music Reference ML134.

Following are some of the work numbering systems in use for major composers. Call numbers for most composers not appearing on this list will either use opus numbers or are not numbered at all.

Bach, Carl Philipp Emanuel
Thematic index numbers used for this composer are those assigned by E. Eugene Helm. They begin with "H." followed by a number. (NOTE: "Wotquenne" numbers beginning with "W." were formerly used for C.P.E. Bach and are now obsolete.)
M1121 .B18 H. 445 1973
M25 .B105 H. 284 1954

Bach, Johann Christian
The composer's own opus numbers are used.
M1001 .B16 op. 3, no. 3 1972
M202 .B2 op. 18, no. 5 1900z
(NOTE: in the above examples the second number indicates the numbering of a work within a larger set. For example, "op. 18, no. 5" means the fifth work in the set of six works collectively labeled opus 18).

Bach, Johann Sebastian
Bach's works use the numbering system created by Wolfgang Schmieder. These used to appear as "S." followed by a number, but the current system uses "BWV" instead.
M2010 .B2 BWV 234 2000
M25 .B11 BWV 802-805 1947

Beethoven, Ludwig van
Beethoven assigned opus numbers to most of his works, and these are universally used. A relatively small number of works lack opus numbers, and these use WoO ("Werke ohne Opus") numbers assigned by Georg Kinsky.
M23 .B414 op. 10, no. 1 1923
M25.B44 WoO 83 1970z
M452 .B4 op. 132 1911
M1001 .B4 op. 55 1900zb

Dvorák, Antonín
Thematic catalog numbers used for Dvorák's string quartets and works without opus numbers were assigned by J. Burghauser, and consist of a "B." followed by a number. Otherwise the composer's own opus numbers are normally used.
M25.D9 B. 129 S9 1989
M221 .D98 B. 81 1975
M452 .D98 B. 121 1955
M512 .D994 op. 81 1989
M1001 .D97 op. 70 2000

Handel, George Frideric
Thematic catalog numbers are from the Händel-Handbuch, and consist of "HWV" followed by a number. However, several major categories (such as the concerti grossi) may still use Handel's original opus numbers between op. 2-7.
M13 .H35 op. 4 1956
M244 .H3 HWV 295 1970
M1122 .H14 HWV 287 1900z
M1040 .H13 HWV 318 1965
M1040 .H13 op. 6, no. 6 1907

Haydn, Joseph
Thematic-index numbers are those created by Anthony van Hoboken, and begin with "H." followed by a Roman numeral, a comma, and a number. Within any given call number these will be filed first by Roman numeral, and then by number within that Roman numeral.
M312 .H39 H. XIV, 6 1977
M1001 .H4 H. I, 27 1963
M1049 .H35 H. IX, 7 1970

Haydn, Michael
Thematic index numbers most commonly used are those of Lothar Herbert Perger, and consist of "P." followed by a number. A newer numbering system is making inroads, consisting of "MH" followed by a number.
M1029 .H26 P. 134 1977
M1049 .H36 P. 72 1989

Mozart, Wolfgang Amadeus
Thematic-index numbers are those assigned by Ludwig Köchel, and consist of the letter "K." followed by a number. Several different "Köchel" numbering systems have been used; currently those in boldface in the 6th edition of Köchel's Chronologisch-thematisches Verzeichnis are used.
M312 .M9 K. 254 1920
M1001 .M92 K. 550 1967

Schubert, Franz
Thematic-index numbers are those created by Otto Erich Deutsch, and consist of "D." followed by a numeral. Schubert himself assigned opus numbers to some works, and these are still occasionally used.
M23 .S384 D. 959 1997
M1001 .S373 D. 417 1970z
M1621 .S38 D. 776 1929

Schumann, Robert
Schumann did a thorough job of assigning opus numbers to his own works, and these are used almost exclusively.
M512 .S397 op. 44 1970z
M1001 .S394 op. 38 1998

Telemann, Georg Philipp
When possible, numbers from the Telemann-Werkverzeichnis (TWV) are used; these begin with "TWV" followed by a numeral, a colon, a letter and a number. The first number after "TWV" is the general type of medium, the letter after the colon is the key of the particular work, and the following number is the numbering within that type of work. In the case of works for which the TWV numbering has not yet appeared, a key ("D maj.", "F min.", etc.) may appear in the call number instead to distinguish works for the same medium.
M312.4 .T3 TWV 42:C3 1998
M312.4 .T3 TWV 42:h7 1998
M312.4 .T3 TWV 55:g8 1999

Vivaldi, Antonio
A bewildering variety of numbering systems have been used over the years for Vivaldi's works. The system used in the UNLV Music Library is that in Peter Ryom's Verzeichnis der Werke Antonio Vivaldis, and consist of "RV" followed by a number.
M312 .V83 RV 83 1950
M1134.R4 V5 RV 443 1951