Poli︠a︡rnyĭ Ural : Lednik MGU : aktinometricheskie i gradientnye nabli︠u︡denii︠a︡, abli︠a︡t︠s︡ii︠a︡, stok - Lebedeva, I. M. (Materialy gli︠a︡t︠s︡iologicheskikh issledovaniĭ., 1963)