Subspaces of trigonal Riemann surfaces (Q912937)

The paper continues the study of trigonal Riemann surfaces, \(y^ 3=Q(x)y+R(x)\), of genus \(g\geq 5\) which was begun in the author's joint article with \textit{R. Horiuchi} [J. Pure Appl. Algebra 50, No. 3, 271--285 (1988; Zbl 0649.14009)] where such curves were classified by the type of the ramification points. The author shows how to determine the genus, kind and type of ramification points for a given equation. Then considering the sets of trigonal curves given by their kind and numbers of ramification points of types I and II as subsets of the Teichmüller space some incidence relations are proven.