Proper holomorphic mappings from strongly pseudoconvex domains in $\mathsf{C}^2$ to the unit polydisc in $\mathsf{C}^2$.

B. Stensones, “Proper holomorphic mappings from strongly pseudoconvex domains in $\mathsf{C}^2$ to the unit polydisc in $\mathsf{C}^2$”., Math. Scand., vol. 65, pp. 129–139, Dec. 1989, doi: 10.7146/math.scand.a-12271.