A priori estimates for prescribing scalar curvature equations (Q1360703)

This is a remarkable paper in the study of scalar curvature equations. There are two important contributions in this paper. One is that they use the Kelvin transform and the maximum principle to derive estimates on solutions in the region where the prescribed scalar curvature is negative. The other is that they use the moving plane method to compare the values of the solution in the domain where the scalar curvature is small. The estimate obtained in this paper is of its own interest, and it is useful in getting at least one solution in the scalar curvature problem.