http://grove.ufl.edu/~chapo
http://students.cs.byu.edu/~glen/
http://www-personal.umich.edu/~bparnes/rockapella/
http://www.unt.edi/~ddas
http://www.unt.edu/~ddas
http://www.accel.com/pac/index.htm
http://www.panix.com/~loren/
http://www.umich.edu/~bparnes/Rockapella/
http://albatross.psu.edu/~panulla/pma/AZ/dreamers.html
http://kogs-www.informatik.uni-hamburg.de/~mueller/sechsr/
http://rescomp.stanford.edu/~pweston/mendicants.html
http://www.artsci.wustl.edu/~cmtess/
http://www.casa.org
http://www.cs.wustl.edu/~seth/a-cappella/RARB/
http://www.icom.it/freeweb/casa
http://www.ing.unipi.it/~s160226/
http://www.ing.unipi.it/~s160226/coro/
http://www.ing.unipi.it/~s160226/coro/index.html
http://www.rootsworld.com/rw/
http://psi.ece.jhu.edu/~dan/html/vc.html
http://www.dartmouth.edu/~boyo/cords/
http://www.juniata.edu/~rhoque