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David Munrow only wrote one book, and it was essentially an accompaniment to two records which acted as musical "illustrations" of specific Early Instruments such as the crumhorn, hurdy-gurdy, sackbut,
lute, et cetera.
He produced something similar called the Mediaeval Sound (a single record) which involved a vocal introduction on each instrument on side one. Munrow believed that discussing such a subject not only required written material, but also musical examples...otherwise it was all rather pointless.
Musica Reservata also did something similar.(see links below)