(Willis). The Dozen a Day books are universally recognized as one of the most remarkable technique series on the market for all ages! Each book in this series contains short warm-up exercises to be played at the beginning of each practice session, providing excellent day-to-day training for the student.
Rather charmingly, but counterproductively, and indeed ironically, the copyright notice forbidding reproduction of the material is illegible... because it's been turned into mirror-writing by the copying process*. [though, oddly, the line above it is the right way round, so presumably was added later - so why didn't anyone notice the backward text just below it!?]
Possibly relatedly: every page carries the initials of one publisher, the front cover and title page have the full name of that publisher and a second publisher, but the back cover carries the name of a THIRD publisher. It looks very much as though each page has been facsimiled from an earlier edition, and presumably the name on each page is the original publisher, but why there are two modern publishers listed, and what the relation between them might be, I've no idea... [book 2 of the same series has the original publisher and the back-cover publisher, but listed on the front cover too, and no mention of this book's front-cover publisher... oh, and book 2 is copyright 1950, while book 3 is copyright 'MCMLIII', even though both copyright notices refer to the 1988 copyright act...]
*I'm assuming. Mirror-writing isn't that easy on older computers or typewriters, but it can happen when copying things. I know some pre-xerographic facsimile machines automatically mirrored everything (so if you were copying text, you actually needed to copy the copy), but I wouldn't have thought that would have been a problem in the late 80s or early 90s, when this was made. But I guess...