Article describing concave hull implementation

Hi,

I understand that PCL uses QHull for creating concave hulls. According to QHull, however, this is not natively supported (only convex hulls are). I was wondering if there is a resource describing how the concave hull is created. I would like this for describing and referencing the process in my work. I am looking through the source files now, but a description would definitely be useful.

Best regards,
James