Fabian Klute, Martin Nöllenburg. Minimizing Crossings in Constrained Two-Sided Circular Graph Layouts. Computational Geometry (SoCG'18) (Bettina Speckmann, Csaba D. Tóth, eds.), pages 53:1–53:14, 2018, Schloss Dagstuhl - Leibniz-Zentrum für Informatik.