Ask our staff anything about our shop or products, or leave your feedback.
Number theory proves to be a virtually inexhaustible source of intriguing puzzle problems - interesting to beginning and advanced readers. Divisors, perfect numbers, the congruences of ...
In the songs and bubble feeding of humpback whales; in young killer whales learning to knock a seal from an ice floe in the same ...
This is Sir David looking at the wildlife that has captured his imagination and enthusiasm over his career in wildlife TV. The sloth is Sir ...