The licence covers printed music publications which are described as:
“Published editions being graphic representations of Musical Works and/or any associated words or lyrics, printed on paper, including musical scores and/or parts, diagrammatic representations, tablature and other ways of representing musical sound and any editorial notes, historical notes or commentaries or other text included in the said published editions. For the avoidance of doubt this does not include Excluded Printed Music Publications, sound recordings neither does it include publications which are made available digitally and subsequently printed by any person.”
Text books made up primarily of text but containing musical examples are not Printed Music Publications. In order to make copies of these you would need to obtain a licence form the CLA (Copyright Licensing Agency).