An article from a periodical (usually peer-reviewed) aimed at the scholarly community.
Why would I use it?
How do I find it?
Use an index.
Get a citation from a bibliography.
Most periodicals you find in RILM will qualify as "scholarly."
To locate articles published prior to 1949, start with History of Music: An Index to the Literature Available
in a Selected Group of Musicological Publications compiled by Ernst C. Krohn (Ref. ML113 .K77 1958).
Some periodicals you find will qualify as "scholarly," but not all. Look at the pages in Searchpath that illustrate
the difference between popular magazines and
scholarly journals. And look at Ulrich's.
This is one of the best ways to efficiently find any kind of periodical article
RILM (Répertoire International de
Littérature Musicale)
RILM also includes dissertations, chapters from books, etc. You may also use these as sources.
Music Index Online
EbscoHost
The Music Index (paper)