For anyone who is interested in learning more about Mackenzie 'The music of Sir Alexander Campbell Mackenzie (1847-1935) : a critical study' by Duncan Barker, a 412 page PhD thesis can be accessed and downloaded (in two parts) from:
http://etheses.dur.ac.uk/1441/ (http://etheses.dur.ac.uk/1441/)
http://etheses.dur.ac.uk/1441/1/1441_v1.pdf (http://etheses.dur.ac.uk/1441/1/1441_v1.pdf)
Barker wrote the sleeve notes to the 1998 Hyperion release of Mackenzie's Violin Concerto and Pibroch Suite.
This is an excellent study (indeed the only one) of Mackenzie's music and it's good to see it getting wider circulation - I obtained a paper copy several years ago from the BLDSC via the British Thesis Service.
;D
A really useful study and many thanks for the link.