http://mathworld.i2p/Rule.html
See also Algorithm , Boole's Rule , Chain Rule , Cramer's Rule , Descartes' Sign Rule , Durand's Rule , Estimator , Euler's Rule , Euler's Totient Rule , Golden Rule , Hardy's Rule , Horner's Rule , Identity , L'Hospital's Rule , Leibniz Integral Rule , Method , Osborn's Rule , Power...