Multiple Publications, Different Authors
7th Edition6th Edition

When citing multiple authors for the same information, use semicolons to separate the different citations. The authors should be cited in alphabetical order, and, if there is a need to cite more than one source by the same author within a citation for multiple publications, place the years of publication in chronological order (oldest to most recent).
Example:
A recent study argued for the abolition of social class (Calvert, 1987; Liu, 2004, 2005; Smith, 2003).

Follow the rules for one author, and use a semicolon to separate articles. The authors should be cited in alphabetical order, and the years of publication in chronological order.
Example:
A recent study argued for the abolition of social class (Calvert, 1987; Liu, 2004, 2005; Smith, 2003).