unless you want to count Gabo as the creator of the mobile (insofar as he created moving sculptured before Calder did).
I wasn't linking Calder to miro because his work was similar, I was linking them because they spent time together. For me, to call an artist not explicitly alligned with soviet constructivism a constructivist is doing him a disservice, I refuse to call him a surrealist, even though the latent content of lots of his mobiles is surrealist in nature.. I wouldn't even call Noam Gabo a true constrctionalist, either. The real ones developed stuff like Rodchenko, state art.