Bibliography

§ http://www.soundjunction.org/theviolaabriefhistory.aspa?NodeID=1

§ http://library.thinkquest.org/27178/en/section/1/1.html

§ http://library.thinkquest.org/J001411/cello_history.htm

§ http://www.mathcs.duq.edu/~iben/viola.htm

§ http://www.mathcs.duq.edu/~iben/violin.htm

§ http://www.mathcs.duq.edu/~iben/viocello.htm

§ http://www.mathcs.duq.edu/~iben/doubass.htm

§ http://en.wikipedia.org/wiki/Cello

§ http://en.wikipedia.org/wiki/Double_bass

§ http://en.wikipedia.org/wiki/Violin

§ http://en.wikipedia.org/wiki/Viola