Being new to this site (and only very amateur but very much an enthusiast in this area), this might well be old hat to long-established members so apologies if it is.
I came across the following web-site which might be of interest:
http://music.unt.edu/mhte/node/58
I came across the following web-site which might be of interest:
http://music.unt.edu/mhte/node/58