Denys Fisher sale in Schofields department store in Leeds in 1965. A year later, Fisher licensed Spirograph to Kenner Products in the United States. In 1967 Spirograph was chosen as the UK Toy of the Year. Denys Fisher Toys, which also produced other toys and board games, was sold to Palitoy in 1970 and it was subsequently bought by Hasbro. Through the 1980s & 1990s Fisher continued to work with Hasbro in developing new toys and refining Spirograph. Denys Fisher Toys produced the following toys and games: Denys Fisher Denys Fisher (11 May 1918 – 17 September 2002) was an English engineer
Cone of curves extremal rays of the cone cannot accumulate. If in addition the variety formula_1 is defined over a field of characteristic 0, we have the following assertion, sometimes referred to as the Contraction Theorem: 3. Let formula_48 be an extremal face of the cone of curves on which formula_33 is negative. Then there is a unique morphism formula_50 to a projective variety "Z", such that formula_51 and an irreducible curve formula_8 in formula_1 is mapped to a point by formula_54 if and only if formula_55. (See also: contraction morphism). Cone of curves In mathematics, the cone of curves (sometimes the Kleiman-Mori