I would have to say stonei x sanders pride, or stonei x (platyphyllum x sqnderianum). It just looks like there is alot of stonei in there, more than just a primary of stonei x?. The petals say it has to have sanderianum in it. But the dorsal is almost to white to be sanders pride. Which all leads me to believe it has to be sanders pride backcrossed to stonei. By the way, this is a great flower. Definitely one of the beat multis that I have seen in a while. I would just love to have one that looks like this.