Aalto Paimio chairs, reproductions & Artek versions  

I have two full size reproduction Paimio chairs that were purchased in New Orleans in or near 1980. Both in fair shape and in use. I'm wondering if there is a list somewhere of the reproductions of this chair by various manufacturers. Curious as to what these chair might be worth in current market, if anything. They have the two joints on the "skids" as opposed to the single joint that the artek licenced model has (so I've been told). Any and all information about these chairs, the reproductions thereof, and values would be much appreciated.