Worth every penny, great book..
https://www.amazon.co.uk/gp/customer-reviews/R1AYNTI5G8EJ9Y/ref=cm_cr_getr_d_rvw_ttl?ie=UTF8&ASIN=0995584907
https://www.amazon.co.uk/gp/customer-reviews/R1AYNTI5G8EJ9Y/ref=cm_cr_getr_d_rvw_ttl?ie=UTF8&ASIN=0995584907