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Library of Congress Call Numbers: Music call numbers

Music Library call numbers

This page will help you find items by call number in the Lewis Music Library.

For more information about general call numbers, read the overview.

Printed music

A. Class Mu 

Mu classification numbers for printed music are used for works by one composer. It is arranged alphabetically by composer, then by title and/or type of work: 

Sample call number What the line means
Mu The item is printed music
pts It's a performing format
B393 (Beethoven) Composer number
sop (sonatas, piano) Title letters

B. Class M 

Library of Congress M classification numbers are used for collections of music by various composers [M1, M2, M5-] and for editions of a composer's complete works [M3]. Within these numbers, the music is arranged by the medium of performance: instrumental works, M5-M1450; vocal works, M1495-2199.

  • M2: Monuments, sources, reprints, etc. 
  • M3: Complete and collected works of individual masters 
  • M5-M1450: Instrumental music 
    • M6: One instrument 
      • M20: piano 
      • M40: stringed instruments 
      • M60: wind instruments 
    • M177: duos 
    • M300: trios 
    • M400-900: quartets-nonets 
    • M1000: orchestral, band, etc. 
  • M1495-M2199: vocal music 
    • M1497-M1998: secular 
      • M1500: dramatic 
      • M1528: choral 
      • M1611: songs for one voice 
      • M1627: special songs 
        • M1627-M1853: national (i.e., "folk") 
    • M1999-M2199: sacred 
      • M2000: oratorios, masses, services, etc. 
      • M2018: cantatas, anthems, part-songs, etc. 
      • M2115: hymn, psalm, choral books 
      • M2147: liturgy and ritual

Books about music

Library of Congress ML (music literature) and MT (music theory) classification numbers include most of Lewis Music Library's books about music. Other Library of Congress classification numbers are used for books about topics related to music (e.g., GR for folklore, TK for acoustics). Reference Collection books are located across from the Music Library service desk. 

A. Classes ML and MT 

  • ML13: Almanacs, directories, etc. 
  • ML48: librettos
  • ML50: librettos 
  • ML55: essays, papers, addresses, etc. 
  • ML86: portraits, pictorial works 
  • ML90: writings on musicians 
  • ML93: manuscripts, autographs, facsimiles 
    • ML96.5: facsimiles of composers' works 
  • ML100: dictionaries, encyclopedias 
  • ML111: bibliography 
    • ML128: by topic (e.g., ML128.S-, string music) 
    • ML134: by composer 
  • ML159: history and criticism 
    • ML162: by chronological period 
    • ML200: by country 
    • ML385: by composer (i.e., biography) 
  • ML410: biographies of composers 
  • ML460: instruments and instrumental music 
  • ML1400: vocal music 
  • ML3781: national (i.e., "folk") music 
  • ML3800: philosophy and physics 
    • ML3805: acoustics and physics 
    • ML3845: aesthetics and aesthetic criticism 
  • MT2: history and criticism of theory 
  • MT6-MT950: instruction and study 
    • MT6: general, including appreciation of music 
    • MT40: composition 
    • MT70: orchestration 
    • MT90: analytic guides to music 
    • MT170: instrumental techniques 
    • MT820: singing and voice culture


CDs and DVDs are in Lewis Music Library's closed stacks; request them at the service desk. The call numbers for most music recordings are like the Mu classification system for printed music and begin with PhonCD or DVD. Feature films, ballets, and documentaries on DVD have Library of Congress numbers.

LP records are in storage and may be requested through the “Request Item” button in Search Our Collections

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