Classic balayage of measures and subharmonic functions to a system of   rays
  We construct and apply the classic balayage (sweeping out) of measures and subharmonic functions on closed system of rays in the complex plane with vertex at the origin, including measures and subharmonic functions and infinite order. The need for such a procedure occurs in the study of the behavior of entire and subharmonic functions on systems of rays. The results apply to the complete regularity of the growth of subharmonic and entire functions on a system of rays, the study of the distribution of zeros of entire functions of exponential type of class A, touches upon the incompleteness of exponential systems. The paper contains a survey character sections and new results. 
Bulat Khabibullin, Al'bina Khasanova
math.CV