"singularity of an algebraic variety" . "smooth point" . . "singular point of an algebraic variety" . . "singular points" . "singular algebraic geometry" . . "non-singular point" . "nodes" . . . . "non-singular point of an algebraic variety" . . "nonsingular" . "smooth" . "non-smooth" . . "singularity" . "nonsingular algebraic varieties" . . "singular" . "Singularity" . "Singular point of an algebraic variety" . "singular points of algebraic varieties" . "smoothness" . "nodal cubic curve" . "Singular point, non-singular" . "singularities" . "Singular point of an algebraic variety" . "singular locus" . "singularities of algebraic varieties" . "non-singular" . "singular point" .