Cave of Dzhebel
According to Bernard Sergent , the lithic assemblage of the first Kurgan culture in Ukraine ( Sredni Stog II ) , which originated from the Volga and South Urals , recalls that of the Mesolithic-Neolithic sites to the east of the Caspian sea , Dam Dam Chesme II and the cave of Dzhebel . 
<triplet> Caspian sea <subj> Volga <obj> tributary