Comment It s incomprehensible that a point of such importance Symmetry inflection the solutions and critical points evaluation isn t mentioned within whole article Moreover the circle at Figure 4 is unnecessary dislocated above S s y S omitting even a vertical line up to the center of the circle as done at Figure 2 of New approach by Nickalls R W D see note 29 again Tschirnhaus transformation isn t only unneeded but also responsible for such a failure hence t S 0 doesn t mean that an inflection point S 0 q doesn t exist It seems to me reasonable the unknown t along with the variables p and q to be abandoned in favour of graphically grounded ones which are also easier for memorizing