  For real irreducible algebraic curves of the seventh degree, there are 22
types of singular points of multiplicity six, 174 types of singular points of
multiplicity five, and at least 182 types of singular points of multiplicity
four. For complex irreducible algebraic curves of the seventh degree, there are
12 types of singular points of multiplicity six, 92 types of singular points of
multiplicity five, and at least 92 types of singular points of multiplicity
four. In the final section of the paper, a wide variety of open problems on the
classification of singular points of plane algebraic cuves is explicitly
described.
