diff --git a/@greensC0Dpxy/greensC0Dpxy.m b/@greensC0Dpxy/greensC0Dpxy.m
index 7cab3ef..37ceaa0 100644
--- a/@greensC0Dpxy/greensC0Dpxy.m
+++ b/@greensC0Dpxy/greensC0Dpxy.m
@@ -49,8 +49,8 @@
                 case 'y'
                     singPart = @(z) (1./(alpha - z) ...
                         - 1./(conj(alpha) - z*conj(alpha)^2))/2/pi;
-                    singDz = @(z) (1./(alpha - z).^2 ...
-                        - 1./(1 - z*conj(alpha)).^2)/2i/pi;
+                    singDz = @(z) 1.0/(2*pi)*(1./(z-alpha).^2 ...
+                        - 1./(conj(alpha).*(z-1./conj(alpha))).^2);
                     
                 otherwise
                     error('SKPrime:InvalidParameter', ...