Allan Holdsworth's 10 Most Usable Scales
Allan Holdsworth's own list of his most usable scales, from the 1992 REH video: the formulas, his personal symbols, and the triads, seventh chords and modes contained in each.
Holdsworth's Usable Scales
Every part of this series, in order.
Just for the Curious - 5 More Holdsworth Scales
The five additional scales from Allan Holdsworth's 1993 book 'Just for the Curious', with his own symbols, the notes and the interval formulas for each.