1. F. Riesz and B. Sz.-Nagy, Lectures on Functional Analysis [Russian translation], Mir, Moscow (1979).
2. V. B. Korotkov, ?On certain properties of B-integral operators in L2,? Sib. Mat. Zh.,21, No. 6, 161?164 (1980).
3. V. B. Korotkov, Integral Operators [in Russian], Novosibirsk State Univ. (1977).