Gyulai József; Járai J.: Electric and photoelectric investigations on gap single cristals. In: Acta physica et chemica, (16) 1-2. pp. 21-28. (1970)
Michailovits Lehel; Gyulai József; Járai J.: Surface recombination velocity measurements on surfaces of n-type germanium subjected to various gas cycles. In: Acta physica et chemica, (15) 3-4. pp. 95-98. (1969)