Chipmunk Manual Identity?

Hi all

I have among my Chipmunk documents a few pages of what would appear to be a Pilots Handbook /Manual and would like to know what the full document is and if possible obtain a complete copy. It goes to at least 53 pages and is a UK Chipmunk document as it has the RAF style canopy in the illustration diagrams. The only other clue is that the top of each page is annotated “DOC.No.DH.2.2” to me this implies it could be a De Havilland document but have no clue other than that.

Would be grateful if anyone could throw some light on this

Many thanks