Crystal Tipps and Alistair Crystal Tipps and Alistair Crystal Tipps and Alistair is a British cartoon produced for the BBC. The title characters are a girl and her dog who are joined by their friends Birdie and Butterfly. There are 50 five-minute episodes and a 20-minute Christmas special, all first shown between 1971 and 1974. It was created by Hilary Hayton and Graham McCallum. Michael Grafton-Robinson, a BBC producer went independent setting up Q3 of London to produce the series. The animation was done by Richard Taylor Cartoons, who were also contracted to make the Charley Says and the Protect and Survive public information
The Princeton Companion to Mathematics Compared to the concise and factual coverage of mathematics in sources such as Wikipedia and MathWorld, the articles in the "Princeton Companion" are intended to be more reflective and discursive, and to convey the beauty and depth of modern mathematics. Quoting a passage from Bertrand Russell that "Pure Mathematics is the class of all propositions of the form "p" implies "q"", the editor of the "Companion" states that it "is about everything that Russell’s definition leaves out." The core sections of the "Companion" are aimed primarily at readers who are already familiar with mathematics at the undergraduate level. Much of