Charles Gilpin, Jr., Approximation of the Greatest Root of a Cubic Equation with Three Real Roots, The American Mathematical Monthly, Vol. 13, No. 6/7 (Jun. - Jul., 1906), pp. 140-141 ...

SOME years ago you published some interesting communications in regard to the graphical solution of cubic and quartic equations (vol. lxi. p. 55, vol. lxiii. pp. 515 and 609, vol. lxiv. p. 5). The ...