Graham Gibbs' book Learning by doing: a guide to teaching and learning methods is available as a free ebook in pdf format.
You can also download it from the Oxford Brookes website in epub and mobi formats. You will need to add the book to your basket as if making a purchase, but there is no charge. You will also need an ebook reader.
As this is a reprint you would reference this in the following way:
Gibbs, G. (1988) Learning by doing. Reprint. Oxford Brookes University, 2013.
See the Cite Them Right guidance for further details on referencing reprints.