Discounts again

For whatever reason, prices are down again.  Amazon at $68.23.  Barnes & Noble at $69.15.  Book Depository at $68.22 with free shipping worldwide.  And you can still get 20% off at the publisher with code LYON2017 (that's $64 or £44, plus shipping).

Still looking for more reviews on any site where you might have bought one, please.

Update: those discounts didn't last; but maybe they'll be back.

Nov. 9 update – Amazon's and Book Depository's lowest price yet:  $62.05.

Jan. 1 update – The publisher has sent an updated code good for 20% off through 2018: [not surprisingly] LYON2018 at checkout at their UK or US site.  Amazon's price is only 10% off today.

Jan. 30 update – New low: 30% off at Amazon: $56.36

March 2018 update – New low: 32% off at Amazon: $54.63